Yes, I have done all that over and over. However, I recently started taking cholestyramine and it has helped considerably - I suspect therefore that I have a gallbladder problem.
Have you been able to track down any foods that may be problematic for you? Some of the symptoms you're relating - dizziness and feeling very weak along with the changes in heart rate - possibly could be due to food intolerances. I know you say that it happens with anything you eat, but that's a common perception. When people try exclusion diets - taking out all dairy for example, for several weeks - they often find there's one group that might be the culprit. And food intolerance issues may or may not turn up positive on some of the test results.
I've had the heart tests, all negative. The symptoms happen immediately after I eat.
Dizziness, weakness and tachycardia can be due to a cardiac condition. You can image the heart with an echocardiogram, and evaluate for any rhythm disturbances with a Holter or event monitor.
RUQ pain should be evaluated with an ultrasound or CT scan to exclude liver or gallbladder disease.
This answer is not intended as and does not substitute for medical advice - the information presented is for patients education only. Please see your personal physician for further evaluation of your individual case.
Kevin, M.D.
www.kevinmd.com