Immediately after pressing "purchase" for an album in iTunes, a number "1" quickly flashes next to download icon at bottom of screen. However, album never shows up in "purchased" or "downloaded" files or in my library. I hit "purchase" twice, same thing both times. I'm scared to keep trying, what if all of my purchase attempts suddenly go thru and it wipes all of my money from my iTunes account?!
Check for a download problem by attempting to resume download of purchased items as noted in iTunes: How to resume interrupted iTunes Store downloads
Note that you may want to check and see if automatic downloads are enabled on your iPad as noted here iTunes Store: How to enable Automatic Downloads this may be causing the disconnect of purchasing and not seeing any immediate downloads happening.
If that does not work go into the iTunes Store and check your purchase history as noted in iTunes Store & Mac App Store: Seeing your purchase history and order numbers Clicking the Buy button multiple times, may be resulting in multiple purchases, so be careful and check your account purchase history.