SofaOO,

You need to get assessed by a professional. You could have damage or you could have been triggered into a depression. Depression can cause all of your struggles. Covid can cause the same struggles.

Get a good medical exam. A Physiatrist (Physical Medicine and Rehabilitation) who works with neuro rehabilitation would be good. A Neuro Psychological Assessment by a Neuro Psych associated with a Neuro Rehab clinic or hospital would also be worthwhile.

You just say you hit your head. You don't say how or what immediate symptoms you experienced.

What happened that caused you to hit your head into the wall?

No seeing a doctor right away rarely makes a difference. I doubt it makes any difference in your case.