Is it possible to hit "the wall" one minute into a run?  I don't think I've ever had a worse workout!  My lungs burned, I had zero energy, and I wanted to quit every step of the way.  I managed to do two twelve-minute jogs (and a few shorter ones), but only by sheer dint of will.  And I still don't know how far I'm running.  Unless that display on my treadmill starts working, I'm going to have to head to a track later this week and figure it out.