Please forgive me, as I am not the most mechanically inclined.
I have a 1995 E300D that normally runs like a dream. Lately, however, the accelerator seems to be sticking in the morning. When I start the car, the engine revs at a high rpm and when I tap the pedal to bring it down, the rpms stay high or even go higher. If I put it into drive, the car accelerates without touching the gas pedal. If I switch it back to neutral, the rpms stay very high. In addition, it seems that the transmission is shifting a little harder than normal. I live in Los Angeles and it has been cold(California cold

), but not that cold. Any ideas about what might be going on?
Thank you in advance for any help.