The good news is that it should have backed up your old site with a .old extension, so you should be able to go in with FTP and rename the new one as .new, and remove the .old off the other one.
Ah, I just saw that one of the errors was Disk Quota exceeded. If you’ve turned on a disk quota, you’ll need to raise it, or turn it off. Because the upgrade saves the old site, it doubles the amount of disk space you need. Once you change your disk quota, it’ll take a while (minutes to who knows?) to take effect.