Itunes account, 2 accounts, with the same credit card info on both.?

So yeah, i made my first itunes account, and purchased something, but i think i might have had a typo on the email address, and i put my credit card info on it. So i made another one that works, and same credit card info on that. SO I was wondering, if I purchase an app with money, will it cost double because I have 2 accounts with 1 credit card info? I want some help :(