91 Celica - stalls - need help diagnosing

I have a 1991 Toyota Celica with approx. 110,000 miles, standard shift. Until about an hour ago it ran fine. What just started happening is when the car is in gear and I push the clutch in the car will immediately stall, especially at slow speeds. It will restart without a problem regardless of whether the trasmission is in gear or not, clutch pedal has to be pushed in in either case. If I start the car in nuetral and let out the clutch usually the car will idle although even then I may have to restart it once or twice before it will idle. If I start it and then put it in gear, even if I go just a few feet and then press the clutch in again it will immediately stall. It will sometimes die even at higher speeds when the clutch is pressed in for any length of time. Other than that the car shifts and seems to run fine even at highway speeds. Any ideas?

The only thing that happened about a half mile or so before this started happening was I missed a shift, didn’t quite have the clutch in far enough when I went to shift from one gear to the next and had it grinding for a second or two



Anybody? BTW: 1990 Celica, not 1991, in case it makes a difference.