I have severe pain in my left abdominal, right under the ribcage. I was told there were "small diverticulitis" found in colonoscopy but otherwise normal. I was diagnosed with "functional GERDS" but I tend to disagree. Meds help with chronic IBS symptoms and I have regular bowel movements so long as I take meds. I sometimes press in my left side and rib area and I feel and hear gas. Like it is trapped right there. What would this be called? Is is a symptom of GERDS? Also what does "functional" GERDS mean anyway. I am lucky and blessed to have the GI doctor I have, he is considered one of the best at a research hospital but I think he may have called this condition wrong. I have had IBS for over 20 years with severe constipation. I have been on Prevacid every since it hit the market. The pain comes and goes, last for about two-three weeks, goes for a month or so and returns. Always on the left side. Someone else suggested gallbladder? Wrong side I think. Help!!