head spins and dizzy spells

I had my worst dizzy spell and head spin in a long, long time this morning. It started around 7:20am, which was about 1/2 hr. after I took my morning dosage. Walking down the stairs (we live on a 5th floor walk-up) was a little bit of a challenge, but not too bad since I know exactly how many stairs we have and have handrails. I made it down the street, on the subway, down to Starbucks, and up to my office (though granted much slower than usual). I'm still in half an hour before most everyone else. But I hate feeling like ass in the morning like this.
Hopefully it will pass soon.