I'm really surprised you weren't scoped pre-op. But anyway, there is nothing to it. A little IV is the worst of it. You take a very sweet nap, wake up, and go to breakfast. Really. I work in the GI department of our hospital and it really is not a big deal. The procedure is very short, but you wake up feeling great.
The thing is it's really the only way to know if there is an ulcer, and you do want to know this. You don't want an ulcer to go on and get worse. They are treatable, but it's always better to find out sooner than later.