oh no,cam belt?

[scooby111]

I had my cam belt replaced on Friday. It's the first time I've drove car since I thought sounded noisy not the same as before. I got to my destination and it stalled .I tried to restart it but it wouldn't. I rang the garage that did the belt and water pump, they picked the car up and took back to the garage.
Now I'm waiting for news,the car drove fine before .I could be wrong but I thought it sounded worse with lower revs