Transmission or Torque converter slipping?????
Compare the trans fluid level with the engine off and the engine on. With a good pump the level will drop about 1" on the dipstick.
Definitive way is to connect a pressure gauge to the trans.
Until the Internet lets remote people get their hands dirty working on your car, I don't think we can help you much more.

Please give us an update when you learn what actually did happen.
Good luck.





