My 15-year-old cousin definitely has Asperger's, by my diagnosis (I've dealt with lots of them as kids, since I taught high school), but his family has never admitted it or done anything about it. They are Asian and the burden of shame/honor is on them far more than the duty of helping their son adjust and have a social life, so they have always just treated him like normal and not made him do anything different. I don't know if that was a good idea or not. We as Americans love to diagnose ourselves and others with having disorders, and get them fixed as soon as possible... but for my Thai family, that's the exact wrong thing to do. I could never figure it out.
Anyway, he has always been a genius (he's currently a freshman in college, after basically skipping all of high school to do early-entrance) but has never had any friends. Or, the friends he had didn't stick around long because they didn't know how to deal with his quirks (and he has always been in gifted classes with other nerds, but he still didn't fit in). He has several tics, such as hand-flapping and doing the air-typing thing mentioned in the OP, and he used to talk to himself out loud quite a bit too (usually repeating the same thing over and over again). He was obsessed with Star Trek for a long time, though I think he's moved on now. He talks like a college professor most of the time (has always been that way) and is never comfortable around people... usually paces around and never looks anyone in the eye. He has a very hard time expressing any emotion whatsoever, to the degree that he's even aware of it in himself and others.
When he was younger, I used to take him aside to try and teach him how to make friends, how to find something to talk about with his peers, etc. I don't know how much of it stuck. I threw a birthday party for him once and basically made him invite a few kids over, then gave him a soccer ball and got them to kick it around a bit. It was the only birthday party he ever had.
Anyway, don't know why I'm rambling on, but basically I am very familiar with Asperger's behavior and I encourage you (the OP and others here) to pursue treatment for your symptoms. Social anxiety is a terrible thing to suffer through, and I hate seeing my cousin become more and more isolated and entrenched in himself. I fear he will never have a girlfriend, let alone get married, nor will he learn to drive a car or function without his mother, basically. You don't have to go that route.