Can Endometrioma Grow With Each Cycle And Its Treatment?

I am 41, diagnosed with endometriosis 20 years ago. I was diagnosed with a bartholin gland cyst 5 weeks ago and having treating it at home with sitz baths with no sucess. I have had no pain, no fever, no drainage, no redness at all. It was approximately the size of a golf ball and I did feel pressure from it. I had a word catheter placed yesterday and when the doctor lanced the cyst, only dark old blood came out. She wondered if it could possibly have been an endometrioma because of my history of endometriosis. It was also not a classic bartholin cyst in that it didnt protrude from the labia into the vaginal canal, it was deep in the perineum and very firm. The word catheter also fell out today when I had a bowel movement. If htis is an endometrioma, will it continue to grow every month with my cycle? Will I have to have it sclerosed or something like that?