It's my belief that a very large percentage of people with social anxiety are somewhere on the high functioning end of the autistic spectrum which includes aspergers and even add and adhd.
The symptoms of aspergers listed are just that - symptoms. There are so many different ways you can manifest aspergers that diagnosis is uncommon and inaccurate as well.
Having delt with aspergers most of my life, I believe what determines aspergers is fundamentally a filtering problem. It's harder for people with aspergers to make generalizations off raw stimuli.
That's why social interaction is so overwhelming and difficult. In small talk, what people say verbally means virtually nothing. Its all about their eye contact, their posture, their tone and their gestures. People with aspergers have difficulty because we usually just focus on what they are saying verbally and we get overwhelmed with everything else. We can't make the generalization by subconsciously putting all the social pieces together like normal people.
Ask yourself how easy do you get overwhelmed with new stimuli? Do you like routine because its comforting? Do you get obsessed with certain things to exclusion of everything else? Do you have trouble learning new things quickly especially when you are shown only part of the full picture? Do you feel like your emotions are more 'raw' then others. If so, it might be worthwhile to do some research on it.
I have exactly this problem, I can appear quite normal until people start joking around and just talking rubbish. I don´t know how to react. Common misunderstanding of asperger is, they don´t understand joke or metaphors, which I perfectly do and like humour. But what they are talking about 1. doesn´t make sense, 2. isn´t even really funny. I get no pleasure from it because I lack the software in processing nonverbal cues which small talk is all about and nothing else. My only weapon to deal with it is intellect, in order not to appear completely stupid I try to process that rubbish by brain to know what to say. I can do with it a bit, but very soon it gets too much, I get overwhelmed by all that nonverbal and verbal stimuli, my brain shuts down and I´m just staring failing to react. Then people think I am somewhere out, in my dreams... And I feel completely stupid, like a retard. (Which I guess I´m not, sometimes I think on the contrary, I understand things which other people don´t, learn quite easily etc., sometimes I feel I process the information like computer). That´s why I don´t go to parties and avoid social situations. It´s not really fear, even if I didn´t fear it, my brain is not built properly enough to deal with it. Esp. when I´m in social situations all day, it makes me terribly drained, tired and I have to go to sleep early. Perhaps you can cure people who are only shy or have any other disorders, but this is an inborn disorder of brain, which I know is not curable. (I even feel it). They prescribed me Risperdal which I guess will only sedate me down (which I don´t even need), but can´t change that structure of my brain.
One more thing I found is, this disorder is often caused by exposure of mother to "terratogenes" in early pregrancy. Sorry I don´t know exactly what terratogenes are, I guess some chemicals. Which my mother probably was.
And sorry if I was writing too much about myself I felt like I need to get it off my chest.