You need a vestibular specialist, not a PT who has some vestibular understandings. You need a serious diagnostic work up. A PT usually responds to the diagnostic and work-up of a specialist.

You need to dump the PT until you get a proper diagnosis. You may look for a Physiatrist (Physical Medicine and Rehabilitation) to help you. You can find them at Rehab Hospitals and Clinics.

You have your priorities out of order. You need to find out what is wrong before you even start to consider the future or mistakes of your past.

Yes, you did screw up big time by playing with a head injury. Likely, a trainer or coach should have stopped you from playing. The question is simple. Did you just mess up your future of playing contact sports or have you messed up your future for a full life ? I doubt you have an injury that will prevent you from living a full life. Your choices in the next year will determine how well you future will develop.

Your anxiety is your biggest enemy. You need counseling along with good diagnostics so you can settle down and allow your brain to heal.

My best to you.