I'm confused, think I have Asperger syndrome. How do I know?

Perplexing. Folks with asperger syndrome, for the most part, are socially perplexed. They seem to have most of their difficulties in social situations. Many with aspergers realize they are different then most people. Finding out what one's differences are and being able to make some adjustments relative to certain social nuances can help one function easier and with less anxiety.
Can't answer here. Not knowing your age or the behaviors that are worrying you, it's impossible to say if you do or don't have ad and, if so, whether you need to do anything about it. If life is not working well for you, then find a professional who can review the problems and help look for solutions. One thing: you cannot "catch" ad; so, if your concerns are fairly recent, then that's not the cause.