I am very glad you took the time to ask your question. You probably already realize that it is not common and this is likely the reason behind why you have written us. The discomfort you feel that prompted you to write this email is important to pay attention to.
Self-harming, wanting to be punished, and feeling satisfaction from these desires can be brought on by a variety of reasons. However, the fact that this has been going on for a while means that an evaluation by a clinical psychologist or psychiatrist is warranted. You’ve taken the first step writing us here. Because of your age I suggest you talk to your parents and ask them to arrange an appointment with one of these professionals. I would do this sooner rather than later.