When we're looking for answers, every negative test result can feel like a defeat. However in the case of Wilson's Disease, the negative result is a blessing. Despite treatment, it still has the potential to lead to liver failure and can have toxic effects on the central nervous system.

Even though it's been a long time since your concussion, it is still conceivable that you have PCS and it's contributing to your symptoms. I'm glad that you are getting a second opinion from a neurologist.

I know that your therapist is convinced that your symptoms are so severe that there must be a medical cause contributing to them. It's possible that she's right and there's a missing piece that hasn't surfaced or been identified that's prevented your diagnosis up to this point, but it's also possible that she's wrong. She's a therapist, not a doctor, and she may be doing you a disservice by reinforcing this idea.
You did have milder anxiety and symptoms of depression prior to your concussion and mental health issues can get worse over time. In the past you made peace with the possibility that all your symptoms may be psychological and I know you are on board with treatment based on that idea.

I can understand your frustration. You're not seeing any results from therapy or the lexapro yet, and a medical diagnosis can sometimes mean a quick fix which is much more desirable than waiting for a response from therapy and the right dose of psych meds.
You haven't been on the lexapro for long, and you haven't mentioned an increase. It's good news that you've noticed a slight difference in your anxiety because it shows you are having some response to the med. The lexapro may just need more time and an increase(s) to cause a significant difference. Increases will be made slowly with safety in mind.

Your prescriber probably recommended you schedule your next appointment giving your current dose of lexapro a chance to work in mind, but you can always contact him earlier. If you don't already have an appointment scheduled, make one.

Things will get better with time, Sam. I know it must be hard waiting for answers and improvement. Please try to hang in there.

Kay