What Causes Pain In Incision Site Of Hysterectomy?

I have had a hysto about 12 years ago, it took several diffrent surge ryes before I ended up with a complete, the first thing that happened was I simply had a ovarian cyst rupture on a main artery and had internal bleeding, they did surgery and said if I woke of with a band aid on they were able to cartelize where I was bleed internally then I would wake up to a larger bandage and of course I had the larger band ad, I had endometriosis really bad and also on other overly along with cysteine so the did a simple surgery to see why I had so much pain and said my right overy Had grown partially back and so off to surgery I went, now 12 years later I have had a lot of pain that feels like a Charlie horse above my insistion.i know they said I still have endometriosis that some how was still living on somewhere, I had a surgery for scar tissue about 3 yrs ago and there was so much he said it was to where he almost didn t get his Instruments out and was about to have to open me back up, right one I have sever pain, what can this be causing my pain and Charlie horses if everything already gone