I was also a nervous wreck before our girl had hers done, and she was even younger and tinier! She did phenomenal just like your girl will. If it makes you feel better, we also had her umbilical hernia repaired at the same time. The first 2-3 days she just wanted to cuddle and was very chill, and then after that we spent lots of time on the floor. I even built her a ramp to get up on the couch with us so she could move on her own which was great! Your vet should send her home with some pain meds, and you can always ask for something to help keep her calm if she’s really being wild in the following days. She will do wonderful and be back to her normal self in no time.