Ady,

My off the cuff opinion is a concussion that is brain stem oriented that is effecting motor control. There are specialists (Physiatrists, Physical Medicine and Rehabilitation and some neuros) who are good at observing a walking gait to see if there is evidence of a problem. Some physical therapists are also good at watching your gait.

Anxiety is usually a complicating part of PCS.

But then, you can also just be overly focused on things that pre-existed due to your anxiety.

It is not uncommon for PCS to cause little issues to be magnified such that they appear to be a new problem. Most are not.

The hair growth could be one of those issues. Stress and lack of good sleep can cause hair to grow slower.

So, try to back off from your micro self-diagnosing and just leave the diagnosis as PCS with anxiety complicating the matter. Try to reduce stress in your life, including time spent researching concussions. Such research is counterproductive for many.