I also was told I wouldn't be able to vomit, and was able to. I had a stomach bug at about 1 year post op and 2 and a half years post op. I didn't have any trouble as a result, so relax. It's really in the very early months that the risk is greatest.
I would caution you, though. If you don't have nausea drugs, be sure to get them. The problem is that if you're vomiting you won't be able to keep them down, so I would recommend the Zofran that dissolves under your tongue, or Compazine supposatories.
That way if you do vomit, you can take it immediately (or before, when you start feeling nauseous) and keep from repeated vomiting episodes. Although you can vomit, it's still desirable to keep from over-stressing your wrap. Some stomach bugs are quite severe and you could vomit for hours. That would be something to avoid if you can.
Glad to hear you can vomit! It's definitely an advantage.
Hope you're feeling better!