I thought the same, if you have a diagnosed ulcer have they not given you any medication or done any tests like helicobacter pylori or a camera down?
My gastroenterologist is a but sniffy about a diagnosis of an ulcer by a GP without it being diagnosed properly by a camera scan - I guess to make sure that is the proper diagnosis. I must admit, I thought I had a recurring ulcer a couple of years ago, turned out in the end to be gallstones.
The pain is agony, get back to your GP and make sure you have something in for further attacks of pain and get any further tests you need.