Hi - Did he say what kind of cyst it was?? I have had corpus luteum cysts with both of my pregnancies and they are very common. The first one was quite large and we were almost going to operate to remove it but it went away by itself. The second was smaller and caused no problems at all. I dont think they burst as such but just kind of dissolve!! If you are really worried check again with your Dr.. but if he/she is not worried then I wouldn't be either! Good luck matey! I am sure all will be ok!