Cramps after sex?

Tory • I'm in love with my best friend and I couldn't be more happy.
Hi, I'm wondering if after sex anyone gets bad cramps like hours later? The position was a bit weird because I'm used to girl-on-top or spooning, today we tried doggy. It felt amazing, and he liked seeing my back side... But now I have a HORRIBLE cramping pain and my period isn't even due until next week. Anyone know what's happening?