Scary...

[north woods gal]

Yes, all my life. Comes and goes on an infrequent basis, but I'm aware of it so I can deal with it when it happens. There is a name for the condition though I don't recall it, just now. Some things can aggravate it. Not drinking enough water, letting blood sugar get too low, changing position after being the same position for too long and so on. When happens, I make sure to either sit back down or brace myself against something so I don't fall too hard. By all means, talk to your doctor, though.

[ny biker]

For me dizziness upon standing is a migraine symptom. It does seem to be a blood pressure drop; if I tighten my leg muscles (quads) it usually stops. Eating also helps, which is one reason I gained 10 lbs last year . But I've always felt better within minutes, not hours.

In your situation I don't know if I would wait a week to see a doctor.