You don't know "sore" until you've experienced "postpartum sore." I feel fairly comfortable saying this as someone who couldn't go to school after jumping on her grandmother's exercise trampoline all day, and who finally did the splits at the ripe old age of 32. I've been sore, people, but nothing could've prepared me for the burning ring of fire associated with pushing a baby out. It would be one thing if it was just "down there," but if you're anything like me you'll feel it throughout your entire body. When a postpartum woman says she's "sore," this is what she really means.
I had an epidural with my daughter, but y'all, that sh*t wears off. Maybe that makes it even worse. When the pain medication has worked its way through your body and you're over the initial high of holding your precious baby, the postpartum pain can really knock you off your hemorrhoid-covered ass. Like, what fresh hell is this? That first night in the hospital, I woke up feeling like someone was stabbing me in the taint. You can bet your hospital gown I pressed that call button until my nurse came running.
Exacerbating the entire situation is the fact that they kick you out of the hospital before you feel ready (at least, I felt that way). They hand you some witch hazel pads and send you on your merry way. That means most postpartum care is up to you, and you're trying to care for newborn. You know what's really fun? Needing to change the baby and having to waddle across the room like you have a banana between your legs.
Keep in mind this is coming from a woman who had a vaginal birth. For women who had c-sections, it will probably mean different things entirely, but rest assured, sore doesn't begin to cover what they probably feel postpartum, too.