I've only read the op and to me it does seem you are asking the wrong questions. You have clearly said what you want for yourself, namely that you like it in your new world and then you wonder if you have gone introverted cause you're not hanging out with the "cool" people who get drunk all day no more. This logic doesnt click with me.
I rather think and I experience the same thing, you have went from being a mindless kid to becoming an adult, who tries to get the thing he wants out of the real world. It's often that especially men who changed into a somekind of "responsible life" at some point do look back and wonder if their change in lifestyle was so radical that they might be missing out on things, but to then go back to old habits does in 9 of 10 cases result in you loosing both lifestyles, namely your old lifestyle as you new it changed and the first day you show up drunk at work, you'll get fired.
To answer your question, I dont think your lifestyle has made you introverted, you just havent found a way to attend to your personal needs besides your new lifestyle, rather you compensated your needs with more work. If you try to go new ways, maybe an internet forum with topics of your intrest and if you try to find people who talk your language, you maybe will find people, who already lived thru a similiar situation like yours at some point in their lifes and who can tell you how they've coped with it.