First, don't panic. Unless you have gone and done a bunch of stuff to try and "fix" it on your own, there is almost certainly hope.
Also, you may want to go hang out in the IRC room for a bit.
Atrix IRC Room filled with smart XDA folks
Someone will probably be able to help you there if DG isn't available by PM.
And while you are at it, take some notes as to what went wrong, and the instrutions the guys in the IRC gave you to fix it... then add them as a reply to this thread. That way when someone else pulls the same boner, they can search, find your issue, and use the instructions you were given, and save themselves some stress.