Social anxiety is pretty common for people on the spectrum, especially those who were diagnosed later in life. I guess it probably stems from a lifetime of social situations going wrong and you not knowing why, so you grow to fear them. Plus there is the standard social difficulties added in from AS, such as not liking to make eye contact, not liking to be touched, not knowing how to keep a conversation going, difficulty understanding others' emotions etc.

When people first meet me I am awful, I've been told many a time that people think I dislike them, when in fact I am pretty indifferent about them as I don't really know them yet. I've also had a few 'clashes' with people who have very extroverted personality types. One time at my best friends' birthday party, I was told by her partners niece (her partner is older than we are, his niece is only a few years younger than myself) that we could never be friends and that she would make an effort for the sake of that night but after that would never attend any function I was invited to again. To this day, neither myself or my friend know what I did or said that offended her so much. Online interaction is much easier in many ways.