1998 Ford Escort Vehicle stiop running

I have a 1998 Ford Escort Se. The car was running perfectly fine. It has a new battery, alternator. I had just replaced the spark plugs and wires. 2 days later when I was starting it the car made a strange noise. I turned it off it started it again it didnt make the noise again and it ran perfectly. The next morning the car made an even worse noise while I was trying to start it. This time when I put the the ignition switch to off and tried to start it again it didnt do anything. The vehicle will not turn over. I have people tell me many different problems it could be such as the timing belt, the motor or starting being locked up.