I would not over-think this whole process. Relax a little. Give her some room and time to adjust to the change in her body. This is the first time she's experiencing discomfort and confusion. She may still be under the influence of the medications. If they let her leave, and she stays fairly quiet, just let her be and YOU try to relax. Often pets can sense when you are out of whack so try to relax a little.

She was without water for quite a few hours so I think she may be trying to catch up on the water intake.

Why not curl up and read a book, with her ..... watch a little TV. She and YOU need to relax and get some rest.

I am sure she will be fine.