I'm pregnant and I had rough sex now my stomach hurts what's should I do?

Call your OBGYN. And do what he advises , u may need an ultrasound to nmake suree verything is ok , but common sense would tell u that rough sex is not advisable, esp when u are preg, u should be able to have sex if no problems without having it rough.
Relax. Try to relax and see if the pain eases. You need to see a doctor if pain persists or start bleeding. I am not sure how many weeks pregnant you are, but obviously avoid rough sex from now on.