This is the article that prompted last night's questions. I read this and thought "these seem more like social anxiety".
http://www.buzzfeed.com/erinlarosa/31-unmistakable-signs-that-youre-an-introvert?s=mobile
I don't think being an introvert and having social anxiety is the same thing. I am an introvert because I need down time after social activities. I am not really shy anymore because I have gone through many years of therapy to deal with that. I don't think I can change being drained by people.