Looks to me like the pole broke into two pieces. If that's the case it was probably a scratch or ding in the pole, but your flat takeoff didn't help any.
Brian and Jeff are right about your run, open your stride up and pick up your knees a little more. Also, stay patient on your swing. I don't know how to put it other than your not finishing the swing, so you're not fully rocking back (i hate the term "rock back"). By maintaining your swing a little longer, the pole will continue to move, you hips will be in a higher position, and you make that by over a foot rather tahn coming down on it.
PoleVaultPlanet is coming.....