I have stage one endo and it took about a month for me to feel normal again. The first period that I had was like 27 days. But they said that was due to the change in BC pills. So everyone is pretty different. If you don't feel as though you are healing normally call your doctor that is what they are there for!
I have Stage 1, maybe 2 endo. I had surgery because I had cysts, endo, and fibroids on my appendix. I felt better after a couple weeks. I tend to heal very quickly and that is just how my body works. Every person is different. For some people it takes quite some time to feel better after the surgery. Just be patient and take it easy. Don't do anything strenuous until you feel up to it. I know it's hard, but try not to worry and think about it. Stay ahead of the pain and do things that you find relaxing. Your body just went through a lot!