One way to know if the time is correct with the timing belt is by rising the first piston (piston #1), it have to be at the highest point. You can measure it with the oil dipstick. Now the gears where the timing belt goes, are dots that must be align with the dots in the block engine. Make sure you use a new timing belt, do not use the old timing belt because it could get loose again.

Now, when you crank the engine, listen to way it sounds, if it sounds that it crank way too fast, then it's the timing belt. If it cranks normal, then it's not the timing belt. Make sure everything is in place. Check for fuel pressure and that the sparks are firing up. Also, if you tried to start the car with the timing belt out of place, some engines tends to damage from the inside, and if one valve is damage, your engine won't start.