I didn't eject my iPod Nano 'correctly' and now it doesn't work.

I plugged my iPod nano into my iMac a long time ago, and I just unplugged it, (I forgot to eject it properly). I tried plugging it back in and it didn't turn on. I also tried charging it with a quality power source that works just fine (I know this because I use it for other devices, e.g my iPhone/alarm clock.They never fail). The power cord was plugged in correctly. I also tried charging it on my iPod/iPhone dock and even my iMac and still, nothing. I've also tried turning it on/off and the screen stays black. I'm not sure what to do.