Yup, I used to worry about this too, but you are perfectly normal. When erect your foreskin still covers the head, but you should be able to pull it back and expose the whole head.
If you can't do this, or if your foreskin gets stuck back there and cuts off circulation then you might have tight foreskin, a condition called phimosis.
Enjoy your foreskin man... it contains a *lot* of nerve endings... the kind that are connected to the pleasure centers of the brain.
