Gnex stuck on google screen and backup isn't working :(

[Yarnicus]

Hey guys so last night I went to update to the latest cm 10.1 nightly, I make a weekly backup when doing this but I've never had the need to use it on the nightlies. Well last night the newest version got my phone stuck on the google screen. I went to use my backup and it said no backup was found. I tried to mount storage and put the older version back on and my phone won't mount storage. I've also tried using fastboot to flash update the older version back on and I get this message " FAILED <remote: Unknown Partition>" I don't know what that means, I have well over a Gig of memory left and I don't have partitions set up. I could really use some help