I too have had recent 'dizzy spells'. Tghe first time lasting for about 5 days with some nausea and the second again for about 5 days after a break of 1 week.
I enquired with the Caa as to whetehr this would be an issue in my forthcoming Class2 medical and they grounded me , makign me temporalily unfit to fly.
I now need t o prove to them that the issue will not crop up again before I can fly again.
Absolutely gutted.
the diagnosis is that I have Benign positional vertigo.