I consider myself pretty introverted but I'm also pretty conflict-averse, which means that myth #3 doesn't apply at all, at least to me -- if anything, I tend to be overly polite with people. And I know lots of introverts who are the same way.

The introvert-extrovert axis is a great tool for understanding behavior, but don't just assume that every angle of your personality arises from where you are on that spectrum.