Tonight I was suddenly hit with terrible pain in my lower abdomen, similar to when I have menstrual cramps only much worse, and my period just ended. It is the only symptom other than nausea caused by the pain, and I haven't had any irregularities other than this. A few months ago the same thing happened; it was just temporary, I was in such bad pain that I had to go lie down and I slept for several hours (I was almost done with my period at that time). When I woke up I felt fine. Tonight the pain has lasted about two hours and got better when I laid down for a while then nibbled on a cracker. I have OCD and anxiety so I can't stop thinking that it might be a sign of cancer; everything I find online always points to that possibility. Is this likely a sign of something that serious? Or not? I'd like to put my mind at ease or know whether it's worth going to the doctor to have tests done.