A sore spot where you bumped your head does not mean brain damage. I think your anxiety needs to be treated. It is going to prevent or slow your recovery. Anxiety is toxic to recovery. Please try to forget about the head bump as concussive.

You said "the idea that I set myself back even further was terrifying and saddening." Your emotional response is setting you back, not the minor head bump. Please seek help with your anxiety.

My best to you.