Citizen Erased: My Mac deleted my user account! Please help

The last time I used my user account I was browsing the net and sending an email with the built in Mail app. But I accidentally unplugged the Mac and when it came back, my user account wasn't on the Login screen anymore. I tried using this guide: http://ift.tt/1j3pwLZ

And after trying to recreate the account, nothing happens. So I turn to the Console log to see what's going on, and I get this:

It's like OS X blacklisted my username or something like that. Also, I noticed was that my user account folder no longer has a pretty house on it and instead has that ugly default folder icon.

Anyway, even though this is an old PowerBook G4 with OS X 10.5 on it I hope you'll be able to help me out claim my account back.