New cyst less than 3 weeks after lap

I want to scream. I had my post surgery appointment today. Everything looks great. EXCEPT the fact the ultrasound showed a brand new 4 cm ovarian cyst, again. The doctor wasn't able to 100% determine whether it is a functional cyst or an endo-cyst. I wanted to catapult myself out of that chair. Her theory is that it is hopefully just a simple functional cyst that will dissappear as soon as I start drospirenone with my next period and we're jot going to see in 3 months anymore. BUT we're not sure. 🥲 I hate endometriosis, make it stop.