I second what danicasasha says :) tht exactly hw mine felt
Mine felt like yhe cramps you get after you run really long and hard but it was mainly in my lower back
It feels like period cramps in the beginning but gets worse at the contractions get closer. (you know what a Charlie-horse is? where you get a pain in your leg if someone hits it hard enough?) well it feels like that towards the end but in your stomach lol.. only way I can explain it
Mine felt like severe period cramps.