This week's book giveaway is in the OCPJP forum. We're giving away four copies of OCA/OCP Java SE 7 Programmer I & II Study Guide and have Kathy Sierra & Bert Bates on-line! See this thread for details.
This is a normal thing -- in fact, I have yet to find a person that has been able to upload their assignment the first time they have tried! Consider it some extra time to exercise some deep-breathing and look at your assignment objectively one last time.