Trouble syncing music to iPod 4g iOS 6

I just update from iOS 5 to iOS 6.0.1. The update was uneventful, but when I tried to sync all of my music to my newly updated ipod, nothing happened. The status box at the top of the iTunes window showed that my iPod was syncing, but it said nothing about syncing music, and no music was transfered. Also, the storage display bar at the bottom of the iDevice window in iTunes showed that I had 0 GB of music on my iPod. I tried doodling around with some settings, and when i checked "Automatically fill free space with songs" the storage display bar suddenly showed all of my 22 GB of music. However, I do not want to sync the entirety of my iTunes library, and would like to go back to being able to manually select which songs I can sync. Please help.