Why is my ipod not recognized in itunes and content appears to be lost

I recently connected my ipod to charge, when itunes did not come up I found that it was open by another user on our pc. I went to close itunes from there session But it was frozen. I had to press control alt delete to end task. When it closed I opened it back up in my windows session and found all my content was lost and it didn't recognize my ipod. itunes wants to reset all settings to factory and delete any content that may still be on there. When the ipod is ejected it shows nothing on there but when i plug it in show my ipod name, and some content appears to still be there, in my computer in usb port (G:). Please help I hope I didn't loose all my music!!!