1995 Lumina problem

I am hoping someone can give me some ideas on what could be wrong with my 1995 Lumina. This evening as I was coming up a large hill by my house, the car slowed down and wouldn't accelerate to get up the hill.. At about the same time I heard a loud pop. I finally got the car back home but now I hear a loud clicking sound which gets louder when you start the car and press on the gas pedal. Also, I tried to put the car into reverse and heard a grinding sound. Any ideas?