Is it normal to like needles?

I used to be deathly afraid of needles, syringes, and pins. But after my first blood donation seven months ago, I lost that fear entirely. Then the feeling changed directions. Now I donate as often as I can (once every eight weeks) and I now have a giddy, intense feeling of excitement if I know a donation is coming up soon. I derive an almost sexual pleasure from knowing that I am about to be pierced by metal. I love watching YouTube videos of beautiful young women donating. Even now, with my next donation date a few days away, I feel a hunger in my veins to be stuck with that beautiful, gorgeous extraction needle. I will do what I can to help those in need, but I'm beginning to think I might be enjoying this too much.