Phimosis describes the condition of a foreskin opening that is too tight, making it difficult to pull the foreskin back. The main cause of phimosis is scarring which results from being too forceful in stretching the foreskin over the head of the penis — so don’t do it! Instead, try to let the natural changes that occur during puberty gently stretch the foreskin. However, sometimes phimosis still happens and it’s no one’s fault.
Phimosis can happen to varying degrees. You may be able to retract your foreskin when flaccid (not erect), but you’re unable to pull it down when you have an erection. You may not be able to pull it down at all because it’s still connected to the head of the penis (via skin bridges) or because the hole is too small. No matter the degree of your phimosis, it should always be addressed.
Phimosis can make cleaning the penis, urinating and/or getting an erection very painful. What you can do on your own is try to gently stretch the foreskin opening every day, but if this doesn’t work you should visit a doctor to discuss other ways to stretch the foreskin. They may give you a special medicine to put on your foreskin to loosen things up (or discuss circumcision as a final option if the foreskin will not stretch).