time capsule stopped backing up

so since oct 17th (i havent been able to deal with it since because of other stuff going on) my time machine has not backed up my stuff once. On further investigation, ive noticed that the time machine will remain in the 'preparing forbackup' stage indefinitely and never begin the backup.

does anyone know what steps i should take in attempt to fix this problem? the apple store is well out of the way and i just got back from their today for another issue (ahh!).

Perhaps it's full?

313GBs remaining