People often fail to understand the introvert/extrovert dichotomy. Pretty much no one is wholly one or the other - it's a percentage thing. However, the crux of the issue is whether you feel energized or drained while being around groups of people. Of course, you have days when you just wanna chill by yourself, but are you literally 50/50 on "hang out days" and "chill days"? Probably not. I think most people fall one one side or the other.