2004 Ford Taurus Engine Idling too low

I was driving 60 mph with the A/C on, then it started blowing hot air, I would presume from outside, 20 mins. later after starting up from a stop, the car was slow to move, so I pressed the accelerator and there was a huge jolt, as if the transmission finally engaged, at that time the car didn't feel right, and there was vibration coming through the steering wheel when I was stopped at intersections. The next day, the car would start, but immediately stall out, my remote start is constantly trying to engage the engine. I have no idea what is going on with the car, this is the first time I've ever had problems with the car.