Am I a Bad Friend?

I am the worst about answering text messages and phone calls, and sometimes I wonder if that makes me a bad friend. At the same time, I have a huge introverted side to me, so I need a lot of time and space to myself, after spending time with someone. This is something I can't change, not even if I wanted to. So, is it okay to take the time one needs to recharge? Or should we always reply as soon as possible when a friend reaches out?