No, I wasn't shy I was/am introverted. I STILL get energy from doing that, and many times prefer that. Like sitting down and programming, or taking online classes or doing something that exercises my brain, or simply being alone. I mean I am part of the American Mensa after all, I fit the profile rather well.
I don't always enjoy being around a lot of people but I have learned to manage it better. The same way you can use your intelligence to learn a skill or exercise your brain, you can use your intelligence to figure out how to become more extroverted and function in that environment. And I think that's the takeaway---I am STILL introverted but have figured out how to function better in that environment and be more outgoing and talkative with people, although if I don't know many people I still tend to kind of keep to myself.
I'm pretty sure I know what I am personality wise a lot better than you, so you can cut the psychoanalyzing rubbish you are trying to offer me. If we are talking about Myers-Briggs personality types I am an INTJ for the record over multiple tests taken in a 10-12 year period, meaning it's pretty conclusive.