I'm with Jo*Mar. There are not enough G forces. The maximum G force from an emergency stop is about 0.9 G. That is about the same as sitting on your bed and falling back with your head landing on your pillow.

You may get some neck strain from the whiplash.

Or you may have had a poor night sleep. The anxiety of such a near collision could easily disrupt normal sleep and cause all of your symptoms. Many of us who struggle with insomnia have days full of those symptoms.

Glad you did not collide with the elk. I've lived and driven in elk and moose country for decades. It can be scary to see that dark shadow so suddenly.

btw, The safest way to drive in such situations is to brake hard and stop straight. Trying to dodge the animal causes frequent roll-overs and excursions off the road and down the embankment.

With elk or moose, there is a risk of the animal crashing through the windshield so ducking to the center of the car can be important.

But, the more important concept is to not out drive your headlights, especially in elk or moose country.

Here is an interest page of charts and explanations about braking.

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