Quiet people always know more than they seem. Although very normal, their inner world is by default fronted mysterious and therefore assumed weird. Never underestimate the social awareness and sense of reality in a quiet person; they are some of the most observant, absorbent persons of all.
There is no such thing as a pure introvert or extrovert. Such a person would be in the lunatic asylum.
I'm not a brazen extrovert, but I'm not as blushing or demure as people might think.
When I first read the words 'introvert' and 'extrovert' when I was 10, I thought I was both.