I think you have all ready found what is causing your problem I have had two ulcers in my life one when I was very young did not know that I had it until I got very sick but later when I was about 29 I agreed to participate in a study for a new medicine to protect the stomach because I had had a previous Ulcer but half way through they had to take me out of the study because I started to have pain, part of this hole thing was that I had to have a lot of scopes before I went on the trial medicine and during but when I started having pain they did one early and found that I had a ulcer so they took me out of the study started me on some antibiotics and after a few weeks it went way I had two more scopes to make sure it was gone but the pain would even go into my teeth sometimes into my shoulder this is only what happened to me it wouldn’t hurt to have your doctors look closer also you my want to try some Pepto Bismol when you are here those pains at least you know if’s your digestive System it won’t hurt to try I hope that this helps in someway good luck keep looking if it’s not your stomach then make them get you a good cardiologists to look at everything you have had done