1990 Volkswagen Jetta Grinding and knocking noises

I was driving My 1990 VW Jetta 5 speed, When all of a sudden the car made a banging sound and it Felt as if the engin or the transmission fell out, (I felt it under the pedals and at the gear shift), the car still drives but it makes this grinding noise now almost like its rubbing on something. It also makes a knocking noise when I let up on the gas or put it in neutral to slow down. It doesnt matter if its in gear or not it still makes the noise. I cant see anything Visually wrong when I looked under the hood or under the car. Its made this Loud banging sound and felt like something from the engin fell off about 3 times since the 1st time, which is when the problem started.