My surgery was two days before yours and I am having a similar problem. The scale stayed the same for weeks 2, 3, and 4. Once I increased my calories to 900, the scale started to move,,slowly, but at least its moving. Especially once you start adding more exercise, it is important to increase your calories to between 800-1000 calories.
Hang in there, I know it can be frustrating, but it will start moving again.