Transmission Problems 1990 Olds Toronado

[155thINF]

I have a 1990 Oldsmobile Tororando with 155,000 miles on it. I was going to get the transmission fluid and filter changed earlier this week, before the transmission stopped working. I have had all the previous problems fixed on this car mentioned in this forum. The car runs fine I was driving it around town yesterday with no problems until about a mile from my house the auto transmission was accidentally put into neutral and then quickly into drive and made its last big jerk then completely stopped working. I still feel a jerk when car is put into reverse or any drive gear, but car just will not move anymore. Before this happened the car was shifting perfectly the car had been sitting up for about 2-3 years. Any ideas of what might have went wrong or how to fix problem will be very helpful.