I am not sure about why you got the cyst, but I do know that you may not ovulate every month. My OBGYN told me that when I was trying to conceive a few years back. She said it can happen from time to time. However there a problems like Erilyn said that could prevent you from ovulating at all on your own. I would definately give your OB a call. If you haven't been trying for too long they may not do anything yet. GOod luck!