I was in a lot of pain after my surgery too, but no nausea. Call your clinic for sure for advice for that!
I love my band! I have had it for over 6 months now and I can't imagine my life without it. I love being able to eat a small meal and feel satisfied. I love that it is not compatable with foods like bread, donuts, rice, Pasta, pizza etc.. that is such a big help for me. (Everyone is different though with what they can and can't eat.) I love having much less hunger!
You have some big adjustments to make and a lot of learning to do. I vomit about once a week. Sometimes its on a new food, and sometimes its because of one I know better than to eat at all. Its usually just a bit more than a big burp that brings up only a tablespoon or so of food or slime. (Sorry its a bit gross to describe.) I haven't been sick with gastro or the flu but I'm sure things will work just fine. If it ever happens I do plan on being aggressive with gravol though to try to vomit as little as possible.
Be excited for your new life without much hunger !!!!!