 [ Symptoms ] i have been having bouts of severe stomach pain [ Disease ] in my opinion this chronic pancreatitis you need ultrasonography + check blood is amylase or lipase levels i suppose your doctor already did liver function blood test for gall bladder also one last possibility is deudenal ulcer which require endoscopy yet it is unlikely because you found no h pylori in stool you did a stool test honestly i can see no other possibilities good luck