Help please!!!

Ok so I had my surgery for endometriosis on June 2 and got it removed. I was supposed to start AF on June 8 and didn't. I took a prego test and came back negative. So me and my SO had sex on June 15 because I was having CM so I thought I was ovulating. Well last Tuesday I started hurting and have not stop since. My doc says he don't think it could be the endo returning so quickly. I'm wondering if maybe I'm prego and because of just having the surgery and the egg trying to fertilize if that's why I'm in pain. I have no idea. Has anyone else had this???