Hi. Thanks for your query. Noted your history of stinging pain above belly button or to the right of it and fluttering in the lower abdomen along with gain in stomach weight. The most probable cause of such an occurrence are: - Gastric or duodenal ulcers or gastritis. - Pancreatitis - Liver or gall bladder pathology. - Enteritis and/or colitis. Can be due to IBS that is irritable bowel syndrome. I would advise you the following: Tests of blood, urine and stool. Ultrasonography to start with CT scan of the abdomen Upper GI endoscopy and colonoscopy. Clinical evaluation by a Gastroenterologist If all the tests are normal this is probably an Irritable Bowel Syndrome. If any positive finding, then get treated accordingly o get the cure.