Very Painful Stomach - Possible Ulcer, Advice Please.

Hi there,

I have been experiencing lots of pain at the top of my stomach, just down and to the left of the esophagus and possibly just under the rib cage.

I have had helicobacter pylori before and it was treated with antibiotics about five years ago. A stool sample has showed no hp this time. However the pain is still severe. It is a gnawing pain, that is there almost constantly and I am also starting to feel sick from time to time. I suppose eating helps a little but quite soon afterwards the pain is back. I seem to burp quite alot. The doctor has me taking 40mg of omeprazole, although I am not sure if it is best to take it at night or first thing in the morning.

I have stopped all tea, coffee, alcohol and spicy food and tried to cut out all suger. Although I have been eating bio yogurts. I don't know if I should or should not be doing this. Does anyone know?

I have now been referred for an endoscopy but I don't know how soon that will be and I not sure I can wait with the pain.

Does this sound like an ulcer?
Could it be something else?
What should/shouldn't I be eating?

The pain is quite bad, what are my chances of perforating an ulcer if I do have one? I think I am quite stressed, which makes my stomach worse, which then makes me stressed, I feel locked in the cycle.

Thanks for any help