Why can't I sync music onto my iPod?

I have the 3rd Generation iPod Nano. I've had it for a little over a year, so I'm very familar with how to work it, etc. I've been trying to days now, to add more music to my iPod, but, for some reason, I'm unable to. I'll connect my iPod through the USB Port and my iPod screen will stay stuck on, "Connected. Eject before disconnecting." I've gone under "File" to see if I can click on, "Sync *My name*'s iPod", but that option isn't given. I'll click on "My Devices", and I'll click on "Sync", but it won't sync. I've gone onto the Apple website and I've tried the "5 Steps of Troubleshooting" numerous times, and nothing's working. I have no idea what's wrong with it. What could be wrong with it?


Just as an F.Y.I., my iPod's warranty ended ten days ago as of today. My sister also uses this laptop to sync her iPod Touch.