Have you tried vestibular exercises? My doctor has me doing them, and they've been slowly helping my vestibular system. The idea seems to be to initiate the system (my symptoms flare when doing it, but then go away afterwards) without over-taxing it. You should be able to find some online or from a physical therapist (just start slow). My symptoms have been different than what you described, but it might be worth looking into.

This therapy for me created much pain, confusion and usually a migraine. Making driving home a challenge. With my fog it was too much too fast. Consider readdressing your symptoms with your Dr. about these treatments and your reactions in detail. Remember you deserve proper treatment. With my new Dr. I received a correct diagnose and it was expressed that wasn't the best option for my needs. Each person is different so this may be perfect for you. My issues were my eyes and the vestibular system. My eyes don't converge. Due to the brain not being ready to take on too much I only do two different vestibular exercises per day. Best of luck to you. On this path there is always another gift as the brain learns a new trick or compromise. Remember your brain controls you and sends you sweet messages to slow down and rest. It is working hard to help you. If you don't listen it will put the brakes on. Patience is a virtue. You are not alone He is by your side the whole way. Always ask for help from family and friends pull them in and share your challenges, educate them on PCS/MTBI. I downplay the drama of the pain and suffering. Only my husband knows. Best wishes, Lori