Re: Extremely dizzy since yesterday
The vision flashes suggest to me that this is some type of migraine - do you ever get those? Although you say you don't think it's vertigo, google Migraine Associated Vertigo (or MAV) and see if any of it makes sense.
I have had quite a few spells of vertigo, it just suddenly started out of nowhere about 14 months ago. It happened every month for a couple of months, my gp said it was a type of migraine (I've had migraines with aura quite a few times) and related to my hormonal cycle.
One of the worst things when I had this was if I turned over in bed - it felt like the whole world had turned upside down and my head felt like it was being pulled to the ground, hard to explain. It really felt like there was a strong force pulling my head in different directions. Just wierd! And very scary.
Be reassured by your normal CT and MRI results - but tell your gp what's happening.
xx
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