Q: I redeemed a gift card and then bought an album. How do I know if iTunes charged it to my gift card or to my credit card?

Hello Miraaaaa

The way things are billed is that any available credit from iTunes gift cards or promotional credits are used first and then the credit card is billed last or if there is a remaining balance.

iTunes Store: How iTunes Store purchases are billed

http://support.apple.com/kb/HT5582

iTunes Store & Mac App Store: Seeing your purchase history and order numbers

http://support.apple.com/kb/HT2727

Thanks for using Apple Support Communities.

Regards,

-Norm G.