Hi, I'm new to the forum, but wanted to pass along a similar experience. After my surgery I gained 6 lbs when I got home from the hospital. For the first few weeks I didn't lose weight even though I was eating a ridiculously low number of calories.
Hang in there and give it time. In the beginning I focused on following directions and walking off the gas they used during surgery. That gas was my only real pain. You got this.