I saw the post about your [Mark's] daughter who experienced a concussion from a pretty violent car accident even without the head hitting a solid object. That does help put things in perspective. I'm trying to convince myself that these events are more like going on a rollercoaster where a headache might be a natural response and nausea could be because of stress. The only thing that really startled me was how close my head was to the steering wheel after I moved forward - I probably didn't hit the wheel and it likely would've been obvious; however, I have broken bone(s) before without feeling any pain with the high adrenaline rush of the moment.