I noticed a similar issue on my first purchase. When I got my OUYA, the first thing I bought was FFIII. I knew before even playing it that I wanted it, so as soon as I got to the main menu, I selected purchase. I entered my credit card info and confirmed the purchase. Started a new game, got to the end of the demo and it said I needed to purchase the full version to continue. Confused, I checked my bank account, and low and behold, the purchase never went through. I did the purchase again, not having to reenter CC info, and I immediately got a confirmation email, as well as my bank account being charged. Odd, but haven't had an issue since.