After reset, music synced to Other storage for some reason??

I backed up and reset my iPhone 4 to clear out my Other data (3 GB) so that I could fill it to the brim with music. After reset and restore, the Other data was down to 300 MB, so it seemed to have worked. I then synced with iTunes to get all my music in. Now the Other data is 7.5 GB (which is almost the exact size of all my music files), there is no Music storage item and the Music Library is COMPLETELY EMPTY.

I am quite upset now as I deleted a lot of things for the whole purpose of putting music in my iPhone 4, and now it can't even play a single one.