Try getting to the hole from the back of the ear. I doubt your hole is closed, but rather you're probably having difficulty following the hole with the earring. I have problems like that a lot (my ears are quite pierced). If all else fails, attempt to get the earring in from the front again, and gently swirl the earring in small circles to try to locate the portion of the hole that you cannot seem to get to. Hopefully, the earring will slide into where it's supposed to go after some gently coaxing.
Don't try to repierce your own lobes. If you've tried everything, and you just cannot get the earring through, stop at a local piercing studio (please, DON'T go to a piercing pagoda or stand in the mall) and have them put the stud in. Even though you're only talking a standard ear lobe, I'm still against self piercing, especially if you're inexperienced with piercing. I've seen too many UGLY mistakes in my days.