2001 Ford Mustang - Passenger Window

Hello,
I was putting my pony away for the winter and then this happens. I
rolled down (electric windows) the passenger window and then pushed the
button to close and that's when I heard a jerking sound. Basically the
window look as if the glass fell off the rollers or something. Anyway,
now I can't close the window and the glass looks out of place; like a
train off its tracks. Has anyone had this issue and maybe hints as to
how I can fix it. Thanks again for your help.

Regards,
lewis