This is because you were placed in a state of disconnection during the accident itself. That is evidenced by the time distortion and the calm in your feelings and the thinking you exhibited. It was as though your ability to think slowed down as well. This protected you from the rush of fear and anxiety that normally would accompany a life-threatening situation. This is part of a natural dissociation designed to be protective and allow people to function through the subconscious in a more dispassionate way, and this can be life-saving at times so the body can carry out even a complicated maneuver without being frozen in place, so to speak, unable to act quickly almost through reflex alone, and that has saved many people from disaster by pushing the conscious mind to the side so it does not impede the ability to have muscle memory and the subconscious rapid response save the day.
This, in your case, was accompanied as well by some divine attention to forestall feelings of concern that normally accompany trauma, to some degree, in the aftermath especially. This was analogous to the benefits conferred on the body to prevent major trauma in a physical sense. So the mind was continuing to be sheltered for a time almost to the point of being relatively unconcerned you were lying upside down in a shattered automobile and although this was at the expense of being clear-headed, this was not a liability as the car was not on fire and you were attended to quickly to assist in getting you out of the automobile as you described. So this gentle recovery period served you by blunting the emotional trauma that usually remains and will be imprinted strongly in the akashic record as a trauma event needing healing that can set you up for future accidents of a similar nature under normal circumstances. In your case, this will not happen courtesy of the divine realm’s care of you during the episode and the aftermath, both.