Hope- Hang in there! I was banded on 5/13 and today (5/18) is the first day that I have gone all day without taking any pain meds. I have had quite a bit of pain out of my port site, but all of a sudden last night and this morning it is slowly easing up. Thank goodness!! As far as keeping Water down- I was not allowed ANY fluids after my surgery on Tuesday. Wednesday morning they did a leak check and then allowed me to start on ice chips and little medicine cups of water or juice. Don't be afraid to take as much of the pain meds as you need to get you through the next few days. Afterall, they say if you wait and take it when you are already in severe pain- you waited too late. Keep it under control and it will help you cope through the healing. If you are not able to keep ice chips down, I would definitely call you Dr. You may also want to try SF popsicles. They too will help you with fluids.
Good luck to you and hang in there!!