Annoyed with Firestone they didn't want to look at...

Annoyed with Firestone they didn't want to look at tires until the pressure light came on again, so they could find the leak easier. But my point was I don't want to find out the hard way that I have a flat. I insisted they look it's ridiculous. The point is the light comes on when I'm going to drive and usually don't have time to run to Firestone and wait for an hour. I just don't want to find out the hard way that I have a flat. Also, I had made an appointment at 1 have been sitting here a half an hour and they haven't even looked at my car!