Phimosis? I am assuming that you mean the head, or glans, of your penis is not able to be seen, or that you can no longer retract the foreskin over the glans to reveal it. This is a condition known as "phimosis". It usually requires treatment to correct, either topical steroids or a formal circumcision, because it can become a hygeine issue, or worse, get stuck in the retracted position. Go see your doc!