What does an ulcer feel like?

Anybody have one? I have had absolutely no issues since my RNY, until about a week ago - I had a dump issue ranking about an 8 on of a 10 scale. One of my worst - but not the worst. Since then, I have had a mild pain in my upper abdomen. It felt like a over used muscle at first - which is what I thought it was (since the major dump incident). But then I noticed it has sort of centered as a burning feeling at different times of the day. I especially feel it after eating a certain kind of crackers (salty), after coffee (acid), and I have started to feel hungry (something that happens rarely with me).

All this to have me a little concerned. I'll be calling the surgeon's office in the morning and see what he thinks. But I am wondering if this sounds like it might be an ulcer starting?

Thanks guys.