pain coming back 6 months after excision surgery

i had excision surgery in the spring and they removed endo from my culdesac area. it was only three spots of endo but it was causing me a lot of pain. my main problem was pain with bowel movements and it improved significantly right after my surgery. now it's october and the pain has been slowly coming back. just today i was in excruciating pain just for a normal BM. i started depo provera last month after my endo specialist agreed it would be alright to try it since i can't tolerate oral BC and am nervous about IUD insertions as i'm only 21 and i've never had something invasive done like that before (not including my surgery cause i was obviously asleep for that). anyway, it's definitely helping the period aspect of my endo and i haven't had any side effects but i'm still having pain. my endo specialist told me i could have up to 5 years of zero pain after excision but from what i've heard from other people with endo is that the pain can return after only a few months. i feel so defeated :( i really hope endo isn't already growing again