727 Stuck In Low Gear And Shifter Frozen.

We'll I had an old friend come over to my house so we could work on a car for him. While he was here (and because it was a beautiful day) I decided to take him for a demo ride in the Dart. Of course this included an obligatory burnout. I started my burnout in second gear and banged third at around 4000 rpm. The burnout just didn't seem right so I stopped tried to put it back into first gear but the shifter was jammed in second and wouldn't move either direction. The transmission seemed to be stuck in first gear and there was considerable slippage. I drove the car game like this (about 2 miles) and when I got home I pulled right into the garage and shut it down. I am very worried that I may have damaged the transmission because I pulled the dipstick and I could smell a slight burnt smell. We disconnected the shifter cable and the shifter worked. We tried moving the shifter arm and it was jammed. It appears that it could be in the valve body. I have brand new CRT manual valve body (the current valve body is a Fairbanks reverse manual WITHOUT low band apply, this is why I wanted to replace it). What do you guys think? Is it possible that the issue is in the valve body, maybe a bent valve or actuator and do you think I did too much damage by driving it 2 miles? Thanks for the help guys.