I was at the doctor today and I started feeling light-headed.  Being a macho man, I decided to lean against the table-thingy and play it cool.  The next thing I knew I was waking up in an episode of ER, with my fat butt knocked out cold on the floor and nurses surrounding me trying to wake me up.  Boy, did I feel like a jackass.
The moral of the story is: if you have a doctor's appointment at 1:30 in the afternoon, eat lunch FIRST.
And: if you're feeling dizzy, sit down.  I walked away with a bump on my head but I could have snapped my neck or gotten a nasty concussion.