Duplicated Songs on my iPod?

i broke my ipod screen back in april and i sent it to a place to get it fixed. before that though, they told me to sync my ipod one more time so i loose nothing. well, they broke a cable on my ipod and basically had to reset it. So, in a way, i got a new ipod. i got all my songs on there, but some are duplicated. i have the fourth generation ipod touch, and on the itunes on my ipod, in the "downloads" section, there are several of my songs waiting to be downloaded. i did maybe about 50 because i didn't realize they would duplicate. on my computer itunes, i went to "file; show duplicates" and only about, five songs came up. then i synced my ipod again and those songs still didn't go away! any suggestions, or should i take my ipod to an apple store for help?