1989 Chevy Cavalier car accelerated on its own kinda like a

I had the starter replaced and it ran fine for like the first 2 days of driving short trips to the store and home. Then i was driving about 25mph when it started accelerating all on its own, I tried stoping at the stop sign and the car wouldnt quit accelerating. The whole time the radio was turning on and off and the ignition would beep. I tried to take it out of gear and the rpms just red lined so i parked it and turned it off, I tried to start it after 20 mins and all it would do is make a click click click then it would stop that and the radio would flick on and off. should I call an exorcist or a mechanic? Ive asked a mechanic if he could read the codes and he said its too old to get codes from.