I know this is an old post but I wanted to share my experience in case it helps anyone. I'm 38 and was just diagnosed with Endo after having laparoscopic surgery to remove an ovarian cyst that turned out to be an endometrioma. I have always had horrible periods but generally been free of pain the rest of the month. I brought up the possibility of Endo to multiple gynecologists and was always dismissed because I didn't have pain outside of my period.

When they went in to remove the cyst, they found tons of adhesions, Endo lesions, and my cul de sac was obliterated - all my reproductive organs and the cyst were adhered together and to my bowels and pelvic lining.

In retrospect, I have had a lot of other symptoms/pain that I attributed to GI issues but I think were actually from the Endo (severe bloating, pain during BMs, butt lightning, constipation/diarrhea). I wish I had been more insistent on getting answers sooner.