Q: Can I get iTunes to accept my gift card retroactively for song purchases?

I could not find the balance of my iTunes account so I made 2 song purchases. iTunes still did not show my balance, yet it accepted my purchases, against a negative checking account balance on my debit card, listed on my iTunes account. When I redeemed a gift card for credit and tried to purchase a song, it won't allow me to do so, nor does it use that credit to clear the debt of the other purchases.

Aside from using another payment method (credit/debit card), is there a solution which will allow me to use my gift card balance as I first intended to do?