A Little Over A Year Ago I Had A Total

A little over a year ago I had a total abdominal hysterectomy with bilateral salpingo- oophorectomy due to severe Endometriosis. Just recently I ended up in the ER due to bad abdominal pain and they did a CT with contrast, they came back telling me that I have a hemorrhagic cyst on my left ovary. I argued with them about how I had no ovaries left. Well I went to see my OB that did my hysterectomy & he says that I could be the one of 10,000 women that has ovary clusters from birth that are in there & the ovulation formed a hemorrhagic cyst.. Is this actually possible??