Which doc are you talking to? You should have a nutritionist or dietician after surgery, and that person should give you a menu you can follow with weights and amounts. As to your fatigue, I hope it passes. I think it should, once your body gets used to the drastic changes your body is experiencing. Put your feet up so your ankles don't have to be the point of gravity for fluids your body distributes. I also think it would be helpful to walk, believe it or not. Don't let your body control you. You can control your symptoms by controlling your body. the worst thing to do is remain sedentary. You don't have to move much, but even slight movement like walking in place will get fluids and blood circulating.