How do I tell if I have received brain damage from fumes?

They did renovations in the apartments adjacent to mine. I don't know exactly what they were doing, but a STRONG, PUNGENT smell came in through the vents after they were done.

It smells like thinner, and it gave me a headache.

It's winter, so I can't open the windows without freezing to death, so i've been breathing in the fumes for several hours.

I've just read that these fumes contain VOC's and can give you brain damage.

Is it too late for me? How do I know if it's done irreversible damage to my brain?