Without knowing all of the blood tests that you did have done, generally this would include tests that would give information related to the heart as well. So with that said and with the tests that you have mentioned above, it would be very unlikely to be the cause. Now there are tests that are given to rule out any heart problems, such as the stress tests etc.. which can be repeated every couple of years, but 3 weeks I wouldn't think that at all. Normal full blood work up should be given every year just to make sure things are in the normal range.
Plus with the fact that you took the medication, and have not taken it again in 4 days and symptoms come back, chances are this is related to the upper GI. Which following up with a Gastroenterologist and even possibly having an endoscopy done is what you will need. Which can give the doctor so much more information of what is going on. It's not a bad test, but much worth it. If the 14 day supply is all you were given and have no more, you can try taking a pepic daily which can help some too. Also try sticking to a bland diet as well. No greasy, fried, spicy, chocolate foods, limit caffeine intake along with eating several small meals a day vs 3 larger ones. Try not to let your stomach get empty, this can cause stomach acid to build up as well.
But with your age, and those tests showing fine 3 weeks ago, I wouldn't suspect heart related. But you know your body better.. and the bad part is, Heart problems and upper GI problems do mimic each other. So if you are ever in doubt, then do be seen Hun, it's better to be safe than sorry.
Hope this helps
