2005 Kia Spectra My car died

I was driving my car down the interstate going 75 miles per hour. All of a sudden my air conditioner stopped working. Shortly after it seemed as though my car had dropped into first gear, as while I pushed on the gas it just made a revving noise, but the pressure on the peddle was not affecting my speed. I was slowing down. I also lost power steering. Finally, I pulled over and my car began to smoke under the hood. Can you tell me what might be wrong with that and what I might expect to pay?

I drive a 2005 Kia Spectra. I recently had my oil changed, but when I checked my fluid levels, there was not much coolant left.