It could also be dehydration making you nauseous and lack of protein. I think you have the right idea talking to your Dr tomorrow for their advice. It can snowball on you fast. I have not had the surgery yet but I have read about many folks with nausea issues and more than not it is dehydration. If you can't get in with your Dr and you can't keep things down or get things in, I would consider a stop at urgent care or ER and ask for some IV fluids. It can't hurt to get you hydrated fast and might just be the thing that helps you turn the corner and get some protein down also.
I have seen this with my sister who has not had WLS but has a body in a similar weakened state and had some major digestion and nausea issues. It's like a vicious cycle...feel sick, can't eat, you get behind on fluids and feel more nauseous. You get behind on protein too and that adds to the problem....can't seem to keep anything down, dehydration sets in pretty quick and makes everything worse. I made my sister go to the ER and ask for fluids because she was so miserable and weak from this downward spiral. She ended up with 2 bags of fluid before she even finally needed to pee! Sometimes they will diagnose you as mildly dehydrated and not give you fluids, but mildly might be too much for us, especially with having a VSG. So we might have to fight for it. For my sister, it really made a difference, not right away but 24 hours later she felt a LOT better and things turned around for the better. Might be worth a try if you can't get in with your Dr.
YouTube WLS Channel: http://www.youtube.com/user/NadurraDeb