23 year old male on and off loose stool, mild abdominal pain, excessive gas, bloating, nausea. i concerned peptic ulcer or ulcerative colitis ?!

GI issues: You really need to see a gastroenterologist and have this diagnosed appropriately. Keep records of all symptoms and take these with you to the doctor. Be prepared to give stool samples and undergo upper and/or lower GI endoscopy. Good luck.

Vague GI complaints: This coul dbe symptoms of any number of GI disorders including peptic ulcer disease, infalmitory bowel disease, irritable bowel disease, or pancreatic insuficiency. Chronic infections could also cause this such as giardia. It would be best to have these symptoms evaluated with formal testing to arrive at a correct diagnosis.

Belly issues: These symptoms can be suggestive of irritable bowel syndrome, lactose intolerance, gastroesophageal reflux (GERD), inflammatory bowel syndrome. It is very important too seek the consult of a Gastroenterologist to address your symptoms.