I am currently 18 1/2 years old and I have donated 4 times (and I'm going next week); as often as I have been eligible to. I have AB+ blood and when I donate I like to go with either a group from school, or friends. We make an afternoon of it and get lunch too.
I know that the needle is a deterrent for some folks but it really isn't that bad and it's SO worth it. I always recommend it to my friends, especially ones who haven't gone before.
If anyone reading this hasn't donated before, I highly recommend CBS. They take good care of you for the short time you're there, and the app helps keep track of all of your statistics, and when you can give next.
I take pride in giving blood.