Shayna, a recruiter for 2U, is due in mid-March with her first baby and is a living example that it’s really important to never skip a dose of birth control (BC).

“I've been on some method of BC since I was about 16 and have been lucky enough to not experience the ugly side effects. I grew to rely upon my clockwork period, how heavy it was, and how many days it would take post last white pill for Aunt Flo to make her grand appearance.

"This particular month, I was due to take a work trip across the country that was to coincide with taking white pill number one. I hadn't re-upped on my 3-pack prescription and ended up not being able to before leaving for the work trip... or the week following. 'No worries,' I thought, 'even without the pill, it's going to take a bit for the drugs to get out of my system and allow for me to get pregnant! I'm good.' I got my packs later on that week, popped pill #1 and went about my regularly scheduled life (sex life included).

Fast forward two weeks and I experience the. lightest. period. ever. In fact, I can't call it a period because Aunt Flo was abnormally early, abnormally light, and present for approximately half a day. In my 15 years of birth-controlled periods, I knew something was up. But how could I be pregnant? I've been drugging myself for 15 years! How could seven to 10 days of no drugs mess with me that easily?

Well, I waited until Aunt Flo was supposed to make her appearance and yup, you guessed it, she and her four-day visit did not come knocking. Two days into when her normal visits occurred, I stopped at a CVS on my way into work and purchased four pregnancy tests. I made a bee-line to the restroom and somehow had enough liquid in me to pee on all four sticks. All four of them told me that I was silly to think missing a fortnight's worth of pills wouldn't make a difference. So, there we have it. What tipped me to check was an early, crazy light sprinkle of a ‘period.’”

According to the Mayo Clinic, that light period was most likely implantation bleeding. Implantation is when the embryo settles into your uterine lining, and it can happen around the time when you're supposed to start your period.

Jennie, a stay-at-home mom and owner and founder of Swoon Baby Handmade, will soon have four children — Heidi (10), Hazel (4), Hamilton (2), and the newest baby due in January. And she felt more than your run-of-the-mill sleepiness after a long day.

“In all four of my pregnancies I almost fell asleep at the wheel I was so exhausted. That was my initial tip to take a test, even before I had missed my cycle. I was probably four weeks at the most. I remember sitting in traffic headed home from work, and I rested my head in my hands and almost dozed off! It was a different tired than a bad night’s sleep.” According to Dr. Gerardo Bustillo, OB-GYN at Orange Coast Medical Center in Fountain Valley, California, there's a reason you're so exhausted. He tells Romper that progesterone is "soaring" through your body when pregnant.

Can’t seem to keep your lunch down? Dorie, senior vice president at Strategies 360, proves it may not be the flu. Her baby Hugo was born on Cinco de Mayo 2017, and is aptly nicknamed Hugo de Mayo.

“My period was late, but I didn't realize it for several weeks because I had been traveling for work so much. I had been trying to get pregnant for years, so I thought it was stress-induced lateness. I kept putting off the pregnancy test because I didn't want another negative one in my face yet again. Finally, after not being able to keep anything down for a couple of days, I relented. And it was positive! But I had a stiff drink first.

"It was not long after this test that I puked in a trash can outside the national gallery of art on the way to work. So D.C.”

Bustillo says those raging hormones are to thank again for your nausea and vomiting. Sigh.

Tiffany, a self-titled "domestic engineer," had different tip offs for each of her four children, Ethan Lee (7), Katie-Elise Abigail (4), Lucas Maximus (3), and Noah Alexander (2), which proves that every pregnancy can be totally different.

“Oh, the stories I can tell you. With our oldest, I was laying on the bed and my husband says, ‘there's something in there,’ referring to my stomach. I also had to pee excessively every 15 minutes, and I swear a few drops felt like a river. Plus, I had an absolutely odd craving for orange soda, a drink I had not consumed in more than 10 years. I finally took a test like three weeks later." According to The Bump, you have to pee so much more than usual in the first trimester because your kidneys are expanding and your growing and expanding uterus pushes on your bladder, making less room for it to fill up.

"With the second, I would bend down to pick something up and almost pass out. I just thought I was tired, but later found out I was six weeks pregnant and had low blood pressure." All that blood flow you're used to? It's going to your uterus and the new baby growing in there, according to What To Expect When You're Expecting, so it's pretty common to feel light headed and to get some tingly feelings in your limbs.

"[With the] third, I was on Mirena birth control. I had a really bad toothache, but I had this full feeling for weeks. I wasn't really sure why, but the oral surgeon wanted me to take a pregnancy test because I needed to be on strong antibiotics. I protested strongly, and stated there is no way I could be pregnant. He stated no test, no antibiotics, so I took the test and it was positive. We both looked befuddled, so no antibiotics for me.

"With my fourth, for weeks I kept dreaming of babies, and craving sugar and milkshakes. At first I just thought it was my time of the month, but it went on for 2.5 months. I had a period, and actually went in for my annual check-up and blood work. My doctor comes back in and says ‘and then there were four.’ I was so confused, and then she showed me the test results.”

Sometimes, mom knows best, in stay-at-home-mom Ashley's case, and what is a really sad situation can turn into something wonderful. Ashley has two boys now, Parker (11) and Kent (4).

“I've got a kind of funny/sad way I knew I was pregnant. I'd had a miscarriage before Parker, but the doctor told us to try again immediately, because my body was primed. So a few months later, I wake up puking like crazy and can't stop the entire day. But it was just that one day, so I refused to take a test or get my hopes up. Flash forward to another month or so and I looked like I was smuggling a small beach ball under my shirts. Mom looks at me and says, 'I think it’s safe to take a test now.' By the time I went to the doctor, I was like four-and-a-half, almost five months pregnant.

"I actually had another miscarriage before Kent, but that one before Parker was my worst. I was three months and they had to do a [dilation and curettage procedure] (D&C). With Kent, I was just sick all day every day for eight months straight.”

For photographer Tracy, daily activities made her nauseous, and she felt like she was a bloodhound with her sense of smell. Tracy has four kids: Rayden (21), Kayleigh (17), Sage (9), and Ellasen (8).

“I could definitely smell everything greater, but it was mainly brushing my teeth that gave me the gag reflex that was my trigger. I don’t recall a certain smell bothering me, aside from cigarette smoke. I have four kids (five pregnancies), and yes, it happened with each one! However, the length of time it lasted varied from a couple months to the full pregnancy.” According to the What to Expect website, estrogen is to blame for your overly sensitive sniffer.

Can’t hold your liquor? Might want to take a pregnancy test. Nicole’s daughter Maddie (6) made sure her mom was aware she was in there.

“My friends and I were having a girls' night, and I took a shot and it immediately came back up. It happened twice. I'm by no means an alcoholic, but I am at least capable of having a single shot. Then my boobs started hurting so bad even a shirt hurt. So I took a test, and sure enough... two lines.” Looks like nausea caused by her changing hormone levels were to blame, like Bustillo mentions above.

Sarah, an artist and stay-at-home mom to Hazel (7) and Violet (3), is a great example of how what you think may be a light period could actually be pregnancy-related, and you might want to pee on a stick.

“I get implantation bleeding. So my period starts, but then it just kinda stops. Then a couple days later I get a positive test.” According to The Bump, "Implantation bleeding is a sign the embryo has implanted itself in the uterine wall (home for the next nine months)."

When most people think of pregnancy, they think of being tired all the time and a lot of sleep. For Amanda, a loan processor and mom of Greyson (2.5) and a new baby due in February, it was the opposite that led her to pee on a stick.

“I had insomnia, and I just could not sleep. I would wake up for an hour in the middle of the night and then get up for the day at 4 a.m. or 5 a.m., not being able to go back to sleep anyway."

The American Pregnancy Association (APA) noted that insomnia can be caused by many things throughout your pregnancy, but when it happens in early pregnancy, it looks like hormone changes are to blame.

It was a sign from above that told Shianne, a stay-at-home mom and military wife, to take a pregnancy test one day. She's a mom to Erik (12) and Dominik (3), with a baby girl due to arrive in March.

“So a bit of backstory: First, we decided that since we were moving, we weren't going to actively try to conceive in the month of June, because with a military move there is a lot of unknowns that go on in the moving process. We figured we would just wait until after we got settled to start trying.

"Well, we finally got into our new place after more than a week of complete displacement. It was already July, and my exhaustion and stress level were maxed. So our first night in our new empty house, we hadn't received our furniture from the movers yet, and I had bought some of those instant strawberry daiquiris that you freeze and then squeeze. I was really, really tired that night. My back had been hurting me, and I just was feeling wiped, but I figured it was because we had just moved, and I decided to just drink the daiquiri tomorrow and go to bed early that night.

"I got up the next morning and went to use the bathroom, and I know it sounds bad, but those daiquiris were already on my mind, and I was like screw it, it's summer. I'm on a break, my husband's on leave, kids aren't in school, I am unpacking, I don't care if it's 8:30 in the morning. I'm drinking a daiquiri for breakfast.

"As I was walking to the bathroom, I happen to trip over one of the containers we brought that had our bathroom stuff in it. And a pregnancy test comes sliding out of the box and stopped perfectly right in front of me. Because we weren't actively trying, I hadn't been paying attention to when I was due for my Aunt Flo, but then it dawned on me that it was the day after she was due. So I'm like, I'll take it just in case, that way I can have a drink with no guilt. So I did and it wasn't even the full time and I could see a faint line. As happy as I was that I was pregnant with Gabrielle, I was so mad that I couldn't drink my daiquiri that morning.”

Turns out that Fitbit you always wear can tell you more than how many steps you’ve taken that day. It helped alert Julie, an assistant professor of biology and mama to Annie (4) and Emilia (6 months) she may be pregnant.

“With Emilia, my resting heart rate increased by about 10 beats per minute. My Fitbit tracks it daily, and I noticed it about a week before a positive pregnancy test. It actually stayed higher until about a week postpartum, then went back to normal.” According to the What to Expect, Two Week Wait, and The Bump message boards, it looks like this is a pretty common symptom for early pregnancy. Maybe it's from the increased blood volume being pumped through your heart to your uterus?

When Holly, a DFCS county director and mama to Katie (6), Wyatt (3), and Carter (3 months), couldn’t brush her teeth without wanting to hurl, she knew something was up.

“My dead giveaway sign that I was pregnant was that I gagged when I brushed my teeth. I don't know what it was, but every time I brushed, I had to throw up — which completely negated the point of brushing my teeth. It happened with all three of my pregnancies and it lasted the entire pregnancy. That’s how I found out so early with Carter. I knew at four weeks I was pregnant with him after brushing my teeth one morning.”

Every woman and pregnancy is completely different. Obviously, the surest sign of pregnancy is a missed period for most women. However, do you feel like something just doesn't seem right with you, even before a missed period? You may want to take a pregnancy test.

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