I went back after two weeks. I was extremely tired and wished I had waited at least another 3 weeks. I teach first grade. My energy level got better after the first two months.
I feel the same exact way. I start school on Aug 21. I had my surgery July 19th and right now, I'm nowhere near the energy level required to handle my high schoolers. I'm hoping that I'll be okay at the 1 month mark.