You're doing fine. What a lot of people don't understand is that you actually want stalls. Yes, I typed that correctly. You want to stall. It tells you that your body is progressing through this process. Let's take a look at what your body has gone through lately:
5 incisions in your belly
Removal of 85% of your stomach
Hiatal hernia repair ... ?
Reduction of calories by about 2/3rds
Reduction of liquids by about 1/2
How should the body react? It is going, "WOA! I just lost a lot of incoming resources! I need to remap how I am going to deal with this and start using some local reserves."
Everyone goes through this. It is a good thing. You want your body to figure this out. This will not be your last stall, either, and again, it is a good thing. This is part of the natural progression.