I am worried about your vomiting. I had that too for 3 days after my surgery. Are you able to hold any Water down at all? I had so much swelling that nothing was going past the band so they had to drain the 4 Mls that were in there. THEN I was back in the hospital the next day for 2 1/2 days on IV fluids so I wouldn't dehydrate again. So please be sure to let your surgeon know that you are throwing up, especially if you are not able to hold down water.
On the gas, yes, you have to walk walk walk and we aren't talking about around a track. Just when you get up to go to the restroom, do an extra lap or two, you will feel the difference. Are you able to keep your pain meds down? If not, let your Dr. know.
Sleeping.... the toughest is the first 2 nights. After that I was able to lay on my right side with a pillow right up against my stomach so I wouldn't roll or lean on my tummy. It will be a little or a lot of uncofortable getting in a laying position but once you are there, catch ur breath back and are relaxed OMG it feels so good!! Just try your best to lay down, I promise, you will get comfortable. I still sleep on my right side and I am almost a month post op. Laying on my back, uh uh it just feels weird and I can lay on my left side but it is way more conmfortable on my right .
I hope this helps.... please keep us posted on how you're doing.
Good luck