Call me silly, but a lot of that sounds pretty normal to me, I think the situations you listed would make most people anxious. I don't have any suggestions to make them easier, though, as I'm pretty anxious and tend to avoid "the public" in general, and it sounds like you're much more skilled than I am.

I'm not sure how accurate this is, but I thought social anxiety is more as being a fear of judgement or attack by others that makes you avoid social situations to the point of affecting your life adversely, such as avoiding dating, avoiding public places, not eating/drinking in public, not using public restrooms, dropping out of school or avoiding classes, etc.