On the other hand, I have no problems talking to strangers and most of the time leave a good impression on people, but it drains my energy way more quickly than talkign with people I know well. If I spend half the day pair programming with someone, at the end I have a strong feeling of just wanting to be alone. And during trips, after a few days with friends I miss my home, and usually after around a week with my family.

My point is that you can have no social awkwardness and be good at talking to people, but still have it be an energy drain.