I'm not sure if foreskin is supposed to retract when erect or not. I've done it once and it was pretty painful. It pulls back when it is soft without too much trouble.
Masturbation is okay, though I can't get too passionate in the action or it makes the foreskin start to hurt. I'm a virgin, and I'm not sure if sex will be painful for me or not. Is my foreskin too tight?