Manual Gear Shift Seized Up

[9COOP5]

I was traveling good on the freeway yesterday and all of a sudden the gear shift would not move and I heard a popping noise underneath. I was able to shift gears after a few minutes and move the car, and then the gears were stuck again. Tried again and the same thing I could shift and then the gears would seize up again. The car was towed to the nearest repair shop until Monday, when I can have it looked at. The car still starts and I was able to push the clutch in and out s usual. There was some noises underneath, like clunking, when the car was moving up and back trying to get it to drive and I smelled something burning almost like electrical. When I pushed the gas the last time, the car tried to move but it was like a brick was under the tires and wouldn't move. Hope this description helps and any advice is appreciated.