So long story...i was getting constipated often, and been having this pain for a year, happens off and on and about 2 to 3 times a week. It starts with burning, then gas pressure so severe in my lower left stomach to the low center that I'm doubled over in pain.I always have to go poop when this happens and I feel better after. Been tested for celiac, negative. Had a thyroid test and some test that detects ulcerative colitis, negative. Had a colonoscopy, all normal except for a few diverticuli, but not a lot. So I am trying dairy free. I have been doing better but still have had a few instances of pain this week. It had been since last Friday. I was thinking casein intolerance but now im just confused. The gastro doc says its ibs. Does this sound like any of your symptoms?