Laura, that, being both introverted and extroverted, is what is currently called an “ambivert”. And that’s not that rare at all (my wife is one of them).
About your criticism on Marc Cenedella’s post, I humbly disagree. Historically, there has been much more criticism to introverts than to extroverts. Introverts are the ones usually seen as a “defective” minority, and the extroverts as the ideal. And that’s why reading Marc’s post, with its perversion of a well established preconception, was such a fun to me. I never took it at face value: to me, it was meant to be funny and sarcastic.