Your problem is known as phimosis.
you need to be checked out by a surgeon. you might not have any problem now, but it might be a problem in future. it may cause pain, swelling and even bleeding.
better to get a circumcision done.
and moreover, not to scare you, but still, carcinoma penis is almost always associated with people who have foreskin.
suggest you to be on a safer side and get it checked out by a surgeon.