What Causes Sharp Pain In Abdomen After Sex And Constipation?

this is really embarassing for me, but i have a long history of constipation. in the last few months its gotten worse. this week ive tried milk of magnesia, which worked well, but i think im still constipated. but the embarassing part is, me and my boyfriend had sex for the first time tonight, and i didnt want to tell him about my problem. after sex, i have this horrible, sharp, stabbing pain in my abdominan. im really scared and in so much pain. i was wondering if this could have rupptured my bowels or if i should go to the emergency room? please help.