I've had stomach acid for 3 days only today it's gone away but I still have a burning in my upper stomach and just below and behind my ribs what could this be I've not been able to sleep and I was nauseated and vomiting my doctor prescribed me ondansetron for the nasua and vomiting it's gone but like I said the burning is there and only reduces pain when I take a tums what could this be that I have I've never had stomach problems or any acid reflux issues.