I used to run when I got overloaded with anger and was also faced with the possibility that I would be in even more trouble if I stayed and did something that I couldn't run away from. It wasn't the incident, it was me avoiding the next incident. Most of the time I was right in doing it, but I also lost a few jobs over it.
As an EMT, I would sometimes get the feeling that I needed to be doing things as fast as I could and was failing at it, I found myself running without realising it. I had to stop myself, I needed my energy for clear thought and good decision making. I was torn between the feeling that I was "burning off" the adrenaline in a positive way by using it to get from place to place quickly, and the knowledge that I was sapping my energy, adding confusion and chaos to the scene, and it just plain made me look unprofessional.
moving your feet as fast as you can is the purist form of "flight" not "fight". Nothing wrong with being a human being.