Phobia is defined as "a persistent and excessive fear of an object or situation. The phobia typically results in a rapid onset of fear and is present for more than six months,". In many situations, it's something that's natural to fear, but reaches levels that are unlike most people's apprehensions.
That's how I feel about needles. I can't really explain it, and I don't know why. I try to think back to when the phobia started because I swear there was a time I wasn't so terrified, but I have no clue. As far as I know, one doctor appointment I was fine (comparatively), then the next, I was a mess.
I can sit here and type this and realize that it's a dumb thing to be so afraid of. I know I need shots to stay healthy, and I'd love to get my ears pierced again. I can make all these plans and stay completely calm, but, the moment it becomes more real, I freak out. My body freezes, my heart starts racing, and it's all I can do to keep from crying. I'm now 20, but even the vaccinations I had to get for coming to college were a nightmare.
I mentioned this to a friend of mine, and her response was "just take a few breaths, and you'll be over it,". She didn't mean to offend me in any way, but her response did make me a bit grumpy. When people have a phobia of heights of snakes, most people don't say anything, but people have the tendency to confuse their dislike of needles, which most people tend to have, with my and others' genuine fear.
This is a bit of a baby rant because people have a hard time understanding that irrational fears are just that, irrational. Don't try to push your friends into their fears, no matter what it is, that's not your job. Your job is to give a hug when they're freaked out. It's not something that I can just think "it's not that bad" and be over it. It'll take time, and who knows if I'll ever "get over it", but that's for me to do in my own time, not yours :)