Of course you are. Because you decide to be an introvert.
You decide not to spend time with a group of people because thinking ‘I’m an introvert’ is a great refuge from working on your group assertiveness abilities. You decide not to work on your nervousness in social gatherings because you have ‘I’m an introvert’ label to your rescue. You would rather not talk to people than work on your conversation skills as its easier to choose ‘I’m an introvert, that’s how I always have been,” label than to make a human effort of talking to people. You decide to be discouraged by job descriptions asking you to be a team player and fun person to be around, as you have the luxury of blaming your genetics (if you will) in being an introvert, than trying to be a fun person to be around. You don’t even know how to be a fun person because you never tried to find out, being introvert was easy! You decide to not do the networking as calling yourself an introvert is pretty safer than to introduce yourself to strangers. You’d rather not feel stimulated when everyone else is at parties because ‘I’m an introvert’ offers great escape than to work on being different that what you are. And you decide not to come out of your shell as its glamorous to be an introvert these days.
Well, so be you, unless it hurts being one.