I've had two experiences when I passed out for physiological reasons, that makes the rest so much more fun. I cannot do a lab draw sitting. Maybe if it is only one tube. In fact don't feel so damn good typing this.
Way back when I got the no eat/drink lecture, showed up for a service academy entrance physical. 14 big ass vials later I was done. On the floor orange juice and cookies done. I'm pretty sure I was physically screwed up, I walked around for half the day seeing in black and white with no peripheral vision. I think that was only the 2nd blood draw in my life, the first I was a little kid, they pulled a few units to shove back into me if the surgery went horribly wrong.
Fast forward, the hacks lose my medical record. Well, when you've been in the service 12 years it takes 16 vials of blood to recreate a medical record. One vial and I went casper white, they freaked, I said no, it's okay, just let me lay down. Nowadays they always have something to say about my cholesterol. Well, I rarely get vampired without eating anymore.
I do lab draws and start to feel crappy I just get up and lay down on the floor. I firmly believe in getting there while I can still negotiate with gravity.
I went to donate blood once, was not needed. Out to sea, walking blood bank. Poor dude took 21 units of blood to get him stabilized enough to fly off the ship, no idea how he lived. That's why I fall in love when I see old doddering surgeons who look on the cusp of senility. They just might save your ass after an F-14 wheel amputates one leg at the hip and the other at the ankle.
Still mad about 9/11 and the blood donation racket. For weeks after it was all help out, give blood feel good BS. My bank was right across the street from the local Red Cross chapter. I remember every light on there late night on 9/11, people donating blood, me getting as much of my money out as possible. I was mad then. Anybody with half a brain that watched that knew we weren't going to need a mass blood drive. Yet the nooz was constantly dumbfounded as to why the hospitals weren't filling up with wounded. I'll be mad about a lot of that day forever.
Then again I know a fella from WWII that is still mad at the Red Cross, the back story is some important letter they never got to him. Apparently a lot of people disliked them, they sold coffee and sandwiches, the Salvation Army and USO relief stations were free.
There, a whole thread o' veer in one post. :D