As introverts, we have a finite amount of energy within us that deals with the outside. When that energy runs out we need to find a quiet place and recharge. Every introvert I’ve mentioned this to said they felt the same.
Push too far beyond that limit without rest and we’re headed for trouble and probably a meltdown of some sort. For myself I know how much energy an event will likely require and how many breaks I’ll need to get through it. If I push myself I’ll get exhausted and that leads to Mr Grump coming to the surface. What little filter I have is gone and now would be a really really bad time to ask me my opinion on anything.
Fortunately, I’ve learned to recognize the signs. When I’m in a crowded room and lots of people are talking the sound just starts to become a din and I can get lightheaded. What I do to counteract this aside from leaving is I bring disposable earplugs with me. I carry them in my wallet. Earplugs the American Express for introverts. Hmm marketing idea? The Introvert Survival kit?