My nervous system just short circuits from the idea of blood draw/donation. I start shaking, get super tense, and white out in a minute or so. Also, my veins are not super visible which makes the experience super tense.
It's something that I can't control, and is miserable for everyone involved.
Lol, I feel like I'm very similar reaction-wise. My veins are massive though. I tried once and had to call it off within a minute. I want to try looking away. I seem to function better if I look away.
