Will I Lose My Music?

I have recently bought a new laptop (windows 8) and in the process of copying all of my iTunes music from my old computer onto this one, I realized that there is quite a lot of music on my iPod that i hadn't yet synced to my old computer (it's on the iPod, but not the library). So if I sync my iPod to my new library, will I lose this 'un-synced' music? I know this is a little bit complicated but just wary as it's hours of expensive music that I do NOT want to lose.

Thanks.