Wait, why do I get nervous after talking to someone? And it's just one person?

Quetion
I located someone (who I usually see) to the right direction because I knew they were going in my direction. I stood in front of them looking directly at them, I looked in their eyes, and wasn't nervous speaking, while telling them were to go. The person couldn't hear me well (I guess) so I repeated one part of the direction of where to go. A few minutes later I feel myself shaking, like the scared-type of shaking. But when I was locating them to the direction I was just fine. Why? I just don't get why I get nervous and shaking after talking to a person. And I'm fine talking to others. It's weird.. what could be a cause?
Wait, why do I get nervous after talking to someone? And it's just one person?
1 Opinion