Hi Kid,
Welcome to PC! I'm sorry you're having so many difficulties right now.

I would recommend a 2nd opinion and even a 3rd if you want and can afford it.

I'm glad your tests all came back negative. Great news! Now the not-so-great news is that what you're experiencing is probably anxiety/panic. Depersonalization can be a symptom of anxiety and/or panic. But, good news again --both are very treatable!

I would recommend a consult with a psychiatrist. They are much more familiar with the meds that can help you. Xanax is ok, but it is not the best for anxiety. A longer half-life drug like clonazepam is better. You don't get the interdosal anxiety with this med like you can with xanax and ativan.

Anyway, see a pdoc and get going on the right track. I wish you all the best! Please let us know how you're doing!
Take care,
Okie