Maybe don't panic just yet. There's still plenty of options, but need to isolate what the source of it is, i.e. laptop or iPod. Have you tried your iPod on another pc/laptop and have you tried another iPod on your laptop? I know it means messing about with the songs on the various iPods, but as long as they're backed up it wont be a problem.
There is one more potential issue and that is before all this started did you update to the latest iTunes? A newly upgraded version sometimes opens some sort of computer-freak out-vortex for reasons only known to Apple.
I think the latest version is 8.2, check to see what your version is.