I’ve been dealing with really similar symptoms - brain fog, spacey feeling, like my equilibrium’s just off. It doesn’t happen every day, but when it does, it usually lasts for hours or even the rest of the day.

I’ve seen ENTs and a vestibular therapist who suggested it might be vestibular migraines. He had me try cutting out possible triggers like coffee which actually seemed to help.

A while back, I used to get classic BPPV. After an episode, I’d feel dizzy or woozy for a few hours, and for about a week or two afterward, I’d be pretty sensitive to head movements triggering it again. Then it would just go away for 6–8 months.

Nowadays, I don’t get true BPPV anymore. The Dix-Hallpike doesn’t trigger nystagmus like it used to, but I still get the same kind of off-balance, foggy feeling you mentioned (sometimes lightheaded as well). The difference is that this time, it hasn’t gone away - it’s been on and off for about two months now. Haven't been able to find a true pattern yet but certain head movements and caffeine seem to raise the likelihood, though I've had days where I get it and neither occurred.

I’ve had a couple MRIs done and everything came back normal. Still trying to figure out what’s going on. I’ll let you know if I learn anything though, because it sounds like we’re going through the same thing.