[plutonorm]

I have this too. I'm 40 now and over the years I have come to understand it not as anxiety per se. But more as sensitivity. I am extremely sensitive to body language, emotional content, background noises... Details... When I'm in a large group of people there's so much information coming in that it quickly becomes exhausting. If I've slept well and am generally looking after myself I can do large groups for hours at a time. But if I'm tired, it quickly leads to exhaustion which then leads to confusion and anxiety. I also get classified as extrovert in psych tests. And I do love people, it's just they are generally too intense for my poor overly tuned nervous system. I often think I'd do well with a mood stabilizer/anti epileptic.

[nvarsj]

I believe this is what's considered as a "highly sensitive person". There's some scientific evidence showing that you can identify even babies based on how they react to external stimuli. Basically your brain is hardwired to react more strongly than others - this makes social interactions with strangers quite exhausting, for example. And there is nothing you can do about it - it's just some evolutionary development that occurs in a portion of the population. I recommend looking into it more if you're interested - there is also the book Quiet by Susan Cain.