So it's been a couple of months, and I feel confident in saying that I agree 100% with OP, at least in their (and my) case.

I saw the Neurologist, he seemed completely positive that my headaches would go, and that I should stop taking the painkillers. So, I did, and they did! It wasn't like magic, it took a week or so, but they disappeared after actually doing MORE instead of doing LESS. I was sceptical at first ("but this is post concussion syndrome! Lots of people complain about it online, even reputable sources say it's a thing, so it must properly be an issue!"), but a large part of me wanted to believe in it. I believed, and it went. There was probably a bit of a headache that started from anything else, maybe dehydration, too much screen time, whatever, and my brain just picked it up and turned in to a nightmare scenario.

It's really difficult to overstate how much fear there is around concussion, how much fear I specifically had around concussion, and I believe the fear did more (impermanent) damage to me than the actual knock on the head. I lost 6 weeks to dark rooms and being driven crazy by my mind whirling in circles with half-remembered songs and endless what-if scenarios. I keep coming across 'issues' in my life that I think I overmedicalise and the cycle begins anew.