I just pre-ordered Halo 4, Halo Combat Evolved Anniversary and Mass Effect 3 Collectors addition on Amazon, for a total of approximately $200. I had the spare cash now and figured I should do it now so that when they eventually come out it will feel like a free present :P

HOWEVER it turns out that you don't actually pay until the day of shipping, so I can't pay for the games now.

What happens if I forget to/can't afford to ensure I have enough money in my account at the time of the transaction? Will the order be cancelled? (I am using a debit card, not a credit card)