What does this mean about me?

I get really nervous for weird things like ordering food at a place like Starbucks, an ice cream shop, or McDonald's like when I'm on line I get really really nervous and I start sweating, and my heart beats faster and I go over what I'm going to order until it's my turn to order. Also if I'm walking into a store alone or walking into the library alone the same things will happen and I'll just like run to the back and start wringing my hands from the second I walk in until I find the person I was going to meet. At parties I'll sort of go stand in a corner and be alone feel all those things play with my hands rather violently and usually check my phone a lot so that it seems like I'm doing something until I find someone I know, then I can usually relax and go back to acting normal.