Have you ever looked at the group chat of your friends planning a big get-together party for the end of summer and thought "absolutely not"?
There's nothing wrong with being an introvert! It just means that you have to get more and more creative with your excuses to get out of plans with your friends, or simply be honest with them about the fact that you don't actually have the social energy to spend any time with them. Doesn't mean your not friends. Extroverts don't normally understand that, so here's a few memes that only introverts will understand.
So while you're thinking of your next excuse to avoid large crowds and socializing, maybe consider that you could simply say that you're stuck at home looking at funny videos on the Internet.