You have been traumatized, as much or more so as someone who has had his arms and legs chopped off and is now bleeding out on the sidewalk.
Your ego, your very conception of self, has been savaged. What is you, and what is not? Conceptions of the universe have been shattered.
It's like a bad horror movie where the guy's own arm attacks him.
Your brain is not now functioning in the manner it has most of your life. You have extremely high levels of stress hormones circulating in your system. These (glucocorticoids) will supress hypocampal function and eventually kill cells. This inhibits learning, and even the ability to learn.
These hormones inhibit birth of new neurons (yes that does occur) and make a neuron less likely to survive an insult.
Meanwhile they will cause the amygdala to grow. Expansion and growth of dendrites in the amygdala increases anxiety both short and long term. Enhanced learning in the amygdala files away the memories of trauma permanently in a region far below thought.
I learned about this stuff much later, after I sought it out.
Subjectively, from my experience, you may lose the ability to think. Thoughts travel in endless circular loops. You can lose the ability to distinguish truth and falsehood. Timing and the ability to judge intervals may go. Left turns with an auto were very difficult for me for several years after going through a similar experience. Between looking right and looking left, I couldn't judge how much time had elapsed. So I would look right, left, right, left, right ..., and finally try to go. I totaled one car making a left turn.
I'm better now but there is no doubt that my brain was rewired by trauma. It has been re-rewired since.
You are about 3 weeks into this. You may be amazed at how your body seems to still function without food or sleep. It can't do that forever. I hit the wall at 6 weeks.
I highly recommend getting some medical advice prior to hitting the wall. A psychiatrist is probably the best to see. Not because you are crazy or because your reactions are abnormal, but because you are experiencing a normal psychological reaction to a severe trauma.
Peace be with you.