Abdominal pain and diarrhea for 4 months, headaches sometimes chest pain a lot of burping and some times dizzy. head mri, ct blood cbc ab u/s all fine?

Diarrhea: Consider lactose intolerance and gluten intolerance so try to avoid such foods first. If that does not help, then speak to a gastroenterologist.

IBS .?: You may have ittitable bowel syndrome with a diarrhea component. As suggested you should see a gastroenterologist.

No need 4 imaging te: I don't think the head MRI or the CT scan (of abdomen or any part of the body, for that matter) was particularly high-yield. Imaging studies r helpful when the symptoms r localized to a limited region & thought to b structural; however, with abdominal, chest, intestinal, AND neurologic (headache) symptoms, the problem isn't structural - it's systemic. "Go where the money is" & see a GI doctor.