LOL don't be sorry sweetie...that's when the expertise of the guy comes to play. The dude with a long dick who pushes all the way in is a stupid bastard. A guy who knows will measure the amount of cockage in depending on the stimulation, relaxation and anxiety of the victim...
I think is always better to have extra inches as a backup and to play sometimes. Most girls agree that a long cock is uncomfortable and painful but I'm sure they all will feel at some point the curiosity of playin with a big monster; either to try it fully inside, or just to whack it off and/or lick it.