Consult a gastroenterologist. Its a inflammatory bowel disease with over lap of irritable bowel disease. Discuss with gastroenterologist in detail about treatment options like mesalamine.

Diarrhoea with bloating at your age could be due to lot of reason. However upper GI endoscopy and Colonscopy revealed ulcers which could be due to inflammatory bowel disease. I hope endoscopist has taken tissues from the ulcers for histopathological examination. The biopsy information will clinch the diagnosis. There could also be overlap of irritable bowel syndrome. Detail history taking, examination and routine blood tests is essential so please consult your doctor and gastroenterologist.

Eat at regular times. Don't skip meals, and try to eat about the same time each day to help regulate bowel function. If you have diarrhea, you may find that eating small, frequent meals makes you feel better. ... Avoid problem foods. If certain foods make your signs and symptoms worse, don't eat them....