Parking brake cable snapped?

There's a short cable that runs from the handbrake to a bracket mounted on the underbody to the left (driver's side) of the driveshaft. From the bracket, there are two cables that run to each of the rear calipers. If I had to guess, at least one of the rear cables is seized, and you may have snapped the short one running from the handbrake to the bracket.

If you put it up and ramps or jackstands, you can follow the cables for continuity and see if a cable is broken. That being said, it sounds like you should be ordering a new set of 3 cables. It sometimes takes a while to get them, so order now. Also, check your rear brakes to make sure the e-brake isn't seized in the "on" position. You can manually reset the e-brake by hand at the caliper if needed.