This is a good forum for you to expand your knowledge.

Your typical doctor, neurologist too, does not understand these very complex and subtle injuries. Although one person here (something like lia, it had only three letters) did finally conclude their ailment boiled down to pure anxiety; and anxiety does affect, sometimes profoundly, the symptoms; you may very well still have unresolved damage that will not show up on any scan. For one thing damage to white matter doesn't. Damage is often at the cellular level, e.g. axons. Brain metabolism is altered. So it is believable to me. You sound pretty calm (unlike me!) and if you are, you're probably a good judge of your situation.

Read as many threads as you can. Some here have gone on long searches and finally found professional help focused on concussions -- in particular see the thread "Great Recovery Blog". Me, I'm trolling the internet for research. There's TONS of stuff coming out and the consensus is that PCS and concussions are rampant, overlooked, highly varied, and not completely understood.

Seven months is long enough to put you into the PCS category. Many people here are even further out. Me, I'm just a baby at six weeks though still no end in sight and my injury was pretty minor too. You might respond well to exercise therapy.