Suspicious Ovarian Mass after BC

I had Pagets & DCIS w/bilateral MX over 2 years ago...no other treatments required...(no hormones, no Rads and no Chemo). I am 49 and still having regular menstrual cycles up until 2 months ago....was very, very late. Figured I was just starting perimenopause. Ended up in the ER last week over worst abdominal pain I've ever had. The ER did CT scan w/cont but only identified fluid in the abdomen, unable to see ovary on scan. They suspected ruptured cyst and sent me home. Followed up with Gyn and she said 5cm mass with some solid components. She did blood work which showed my CA125 at 65, and now I'm seeing a Gyn/Oncololist on Monday. On the day of my visit I was gushing blood with a 2month in the waiting period. I also have endometriosis. I did have Gen Testing and had a variant of unknown significance with PALB2...but I am neg on BRCA1/2

How worried should I be? I'm going nuts. Major pain and off work till this is resolved. I have nothing to do but stew in this possible diagnosis. How much does CA125 play in this? Everything I read says NOT an indicator before menopause and can be elevated 2/3 times with menstruation and endometriosis. My Gyn said that tumor like this is rare in someone my age.