They way I understand how it works is this; the test stops you once you have answered enough questions to pass or when your time runs out. So generally if you are stopped with time to spare I think you can assume you passed.
Good job and congrats.
Thats not the case at all. The test stops when it has either determined you have demonstrated a knowledge level sufficient for you to pass in all 6 areas, or you have demonstrated that you dont know enough things an EMT should know in any of these areas, or cannot apply that knowledge in scenarios, to the point you fail.
It may be some of the people who fail ran out of time, I'm not sure, but I'm pretty sure thats not always the case. I was under the impression most of the people who fail still had time left when the program ended the test. I passed the only time I took it so I'm mostly basing this on what Ive read here.