I had labyrinthitis (inner ear problem)(sp?) on and off for about seven years and it was at its most severe for a constant four months. It made me change my career, it induced stress because there were times I couldn't even stand up!

During these four months I had a headache the entire time too!

This actually got me back into flight sims because at the time I couldn't play any Quake style game because it made my condition worse. I'm still rather wary about playing anything like Quake incase it brings it on again although I have been relatively clear for the past 3 or 4 years.
Not a nice experience though, eyes shimmer, you fall over and usually end up bashing your head against something! Ouch!

So yeah, I know what vertigo is like! Only tip I can give is sit or lay down!

It's most probably some flu or cold going around and it's inflamed the canals between your ears and nose/eyes etc., affecting your balance.