Bad gas pain upper ab pain and constipation. negative colonoscopy endoscopy full body ct scan normal blood test thyroid blood work normal. i'm lost?

I'd say IBS like,,,,: I would say that this is a case of ibs or irritable bowel syndrome. You have gas and constipation, with pain. This is a classic presentation. You could likely improve these symptoms dramatically with a diet high in fiber, with vegetables and fruit along with enough protein from meats. More fluid consumption also helps. Best of luck.