Was it an ovarian cyst?

So last night I had a very intense, sharp pain in my lower left side. It hurt so bad that I could barely walk or stand up straight. I called one of my friends who is a nurse and asked her if something was wrong with my appendix and she said if I did, the same pain would be on the right side. I decided to go to an emergency clinic since my doctors office had closed and I was in so much pain plus I didn't want an ER charging me an arm and a leg just to find out it was something minor. I took an ibuprofen and went out to the car. When I got out of the car at the clinic, the pain was gone. What happened?