Your cysts are small and can definitely cause pain. More than likely, they are functional cysts; however, you do have a history with your grandmother's ovarian cancer. I would ask your doctor about watching the cysts closely and monitoring symptoms. If you feel especially anxious, I would suggest getting a 2nd opinion. Good luck!
Cysts can cause a lot of pain, but if your doctor is not worried, and you feel that you can trust him/her, try to relax and not worry too much. If you would like a second opinion, nothing wrong with that. You're cysts are rather small and I'm sure they would have told you if they were anything to worry about. When in doubt, get a second opinion. If it will help you relax, go ahead and get another one. Good luck and try not to worry.