It's A Needle Thing

I went to the doctor's again today to get up to date with all the injections Biola requires me to take.

The last time I went it was to let them take a few vials of my blood.
I don't have a problem with this as much as I probably should. If somebody really needs a few vials of my blood that badly I'm generally willing to go along with it. My rules concerning my blood pretty much draw the line right before anything Angelina Jolie and Billy-bob Thornton are willing to do with theirs. Testing? Okay. Wearing around the neck? Not cool.
I'd probably be willing to give blood if not for one little problem.
Apparently I pass out rather easily.

When I had my blood taken a few weeks ago everything was going along just fine, although admittedly my nurse worried me a bit. As I watched her insert a needle into my skin and witnessed a stream of my blood enter the vial, she looked me in the eyes and said with an accent, "You like to watch your blood, no?"
How exactly she expected me to respond to this, I'm not sure. But as I looked at her I began to realize how grainy my eye-sight had become. It was as if the world had gone from high-definition to 8-millimeter film. Exposure began to go, and suddenly a darkness swirled around me until it seemed as though I was looking through a straw.
"Drink this," I heard. I swallowed, and as vision returned I saw three new nurses staring back at me with concerned expressions.

This time I was given three shots on my arms. It all seemed to be going well until my right hand started aching while the nurse injected me with an Hepatitis B immunization. The familiar black haze started returning, and once she finished I asked to lay down for a moment.

This nurse was one of the three who saw me when I last blacked out.
I couldn't understand. I had seen no blood this time, nothing to make me queasy, but it still happened.
She gave me a cup of water and told me, "It's a needle thing."
Apparently so, but why needles? It seems like knives are something to be more nervous around, but maybe that's just how I am.