Trouble completing album

I was making separate song purchases from the same album, and I noticed the blue complete album button price go lower and lower. After making 6 song purchases, the price of the album got down to $2.25, then I made another single song purchase. Then something strange happened. I got a weird error message and when I backed out of that screen and opened up the album again to complete it, the blue button for "buy" under the album was now white and it was priced back at $9.99, the price it originally was. It was as if I hadn't bought any of the single songs, although they clearly display "play", because I have purchased them. If I hit the buy button to try and complete the album, is ITunes going to charge me $9.99 for the rest of the album, when 30 seconds prior it was offering me the rest of it for $2.25? I'm so confused, and I don't want to rip myself off. Also, I can't just purchase one of the songs I now want because it's included on the "album only"! Any help would be greatly appreciated.

Thank you.