Am I shy and I don't know it?

Factual Questions
1

I am not a shy person, at least, I don’t think I am. Yet, quite often when I’m talking to someone about something I believe very strongly in, I get a little knot in my throat that I have to gulp down. Sometimes I even start shivering like I’m cold.

I don’t know if either is noticeable to the person I’m talking to, but it really hinders my ability to express myself. The thing is, I’m not nervous. I mean, consciously, I’m perfectly confident in myself. Yet, my body exhibits signs of nervousness.

Is there something going on behind the scenes here? What can I do about it? Take a deep breath?

2

I have the same problem. Even when I don’t feel nervous, my body likes to freak out a bit. So far, I haven’t found any successful way to combat this.