It's been happening to me about 1-6 times a week since I was 15. At first, I was pretty scared like most people, then eventually I started to enjoy it. It's so common for me now that most of the time I just shake it off and go back to sleep without trying to go any father. If you let it continue, it does often get too powerful and you can't stand it anymore - or it will crack and you'll be out.
This stage could be the beginning of many fun things for you! Enjoy.