On occasion(once a month, every other month) I will take a nap and wake up in the middle of it with a severe pain in my upper abdomen, stomach area. I usually go to the bathroom and after any where from 30 minutes to an hour or 2 it usually subsides. but sometimes i can feel what are like tiny tremors in the same area hours later. I doesnt happen often and only seems to happen while im asleep, the pain being so great it wakes me up. it tends to happen more often when i sleep curled up. any ideas? my insurance has ran out so i cant really go to the doctor unless it gets really bad. I have really acid reflux disease and while i had a clean flex sigmoidoscopy i still have pretty bad constipation or diarreah from time to time.