Dear patient, the symptom complex that you are describing is most likely due to a functional gut disorder known as irritable bowel syndrome . Although this is a harmless and benign condition but it is very cripling to the patient and equally frustating for the doctors to treate. It is generally found in anxious personalities in whome the anxiety precipitates the bowl symptoms and bowl symptoms then exaggregate the anxiety and the viscious circle sets in . However the diagnosis of irritable bowl syndrome is entertained only when the organic causes for these symptoms have been fully excluded through proper evalvation of the patient because symptoms like feeling of incompleate evacuation of bowl which we call rectal tennismus and oral ulcerations which are most likely apthus ulcerations are caused by some organic diseases of the gut also like inflammatory bowl disease (ulcerative coilitis and crhons disease), diverticular disease, coeliac disease, cytomegalovirus infection (in immunocompromised patients) etc as well as the symptoms like excessive acidity are caused by acid peptic diseases and giardiasis etc. So you should get those investigations as advised by your GP done as well as consult a gastroenterologist who may advise some more test like upper and lower GI endoscopy and barium studies to rule out those organic conditions as mentioned above. Mean while you should take the medicines that your GP has advised as it is the perfectly right treatement. Besides these medications yuo can try some diatery and behavioural modifications like avoidance of smoke and alcohol if you take, avoidance of spicy foods, excessive tea and coffees, citrous fruits, and more use of fibrous diets like green leafy vegetables. If all your investigations come normal then you can try the antidepressant medications like amytryptalline 10 mg at bed time to which this condition (IBS) generally responds very well