Pepro-Bismal is a bactricidal medication. The active ingredient is the element Bismuth, which kills bacteria on contact. Relief of symptoms upon administration of a bactricidal agent helps in diferential diagnosis. It tends to suggest a bacterial etiology, H. Pylori being the usual culpret. You have not provided enough medical information for further comment.
Check for acid reflux, could be treated easily if indeed that is was it is. what did they tell you in the E.R. ? you could also have Dr. check gallbladder, my mother in law had symptoms just like yours and finally they had to remove her gall bladder, she was in the E.R. multiple times, they thought she was having a heart attack, after they removed the gall bladder, she has had no problems.