Telephone Terror

It has been brought to my attention that I am not, in fact, completely 'normal'.
For example, I have been told that normally, people don't have a panic attack by the thought of making a phone call. I do. And despite previous statements to the contrary, people around me have come to realize it is not merely a matter of me 'being silly'. I am genuinely terrified of dealing with people over the phone.

Now I'm aware that many people find phone calls somewhat unpleasant, and I can come up with several reasons why I wouldn't be entirely comfortable with it.
- I much prefer dealing with people face to face, so I can see their facial expressions and body language.
- I'm afraid of being unable to hear/understand what people are saying, and they are unable to hear/understand me.
- I HATE having to lead a conversation. I never know what to say.
- You know that moment after you've dialed a number, before anyone picks up the phone? That moment of uncertainty when you don't actually know whether or not you've reached the person you're trying to get in touch with? That.

Well, these are all reasons why phone calls can be unpleasant, but downright terrifying? That doesn't really make sense. It doesn't explain the way my heart rate doubles and I start shaking when the phone rings, or why I need to sit alone in a quiet room with the door closed, with pen and paper or my laptop (or preferably both) in front of me, trying to control my breathing to stop hyperventilating in order to make a call. These are not rational reactions.

Furthermore, I don't know why I react this way. I can't remember any terribly unpleasant experiences in my childhood, in fact I used to phone people all the time. And I still remember being a kid with my first ever mobile phone. What ever happened? Could calling a wrong number a couple of times really have such a strong effect? I know I was a sensitive child but... really?

Did something happen that I have repressed?