My iPod nano's songs got erased

My Ipod nano got a bit of water damage everything on it seems to be working. The problem is that all of my music appears to be gone, however my ipod is saying that there is 7.1 gb of memory used up. When i checked through the whole ipod i couldn't find anything that could be using up that space and when i plug it in to the computer it says that it can't read my ipod's contents that it needs to be restored is there anyway to save the music in it? Or to fix it so i could get the music out?