sorry you are having this problem. Since the over the counter meds are not working you should see a doctor. They may need to do an Upper GI to make sure you don't have an ulcer. Also, The chest pain and back pain needs to be checked too. I don't want you to put off going to the doctor but it does take a month or two for Zantac or Prilosec to heal an ulcer or you may reflux even if you don't feel it. Please get this checked out.
get off the tums or rolaids, they make it worse. Pickle Juice helps alot. try it and sit up straight and relax just take a couple of sips of dill pickle i like the deli style from sams club. great.. will pray for you , i would go to the doctor and have him help you too..