I have trypanophobia (fear of medical procedures involving syringes). I feel great discomfort in the presence of hypodermic needles, often faint during procedures like immunisations and experience uncontrolled arm spasms and whole body shivers when I think about injections. At least I'm immunised until I'm like 40 years old now. And have no plans on visiting Asia or Africa.
I also sometimes experience episodes of social anxiety that I personally describe as "freak ins", which is like a "freak out" except that I'm screaming hysterically internally. Basically when I'm in a loud and chaotic environment (like a crowded club or whatever) where I have no goal or preoccupation to keep me interested (like an activity or conversation), I resort to an internal monologue where I discuss my own inability to cope with my surroundings. I stay calm and whatever in this state, but according to friends who have seen me in it, I sometimes just sit in a corner staring into blank space anywhere from minutes to hours. Thing is, I never notice how much time has passed during the freak in. Afterwards I just realise that I've been staring at the far wall for 30 minutes.
Worst part is that after somebody snaps me out of it, it me entirely too long to get over it and I have a period of zombie time where I can't adequately talk to people. Which is a bit of a downer when you're out with friends.
At best people think I'm a deep thinking sort of person with a lot on my mind. More realistically people think I'm a nutcase who is really killing the buzz of the area around me.
I'm sorry people around me. It turns out I am a nutcase, but I'm at least trying to be a normal person.
Most of the time I succeed in the illusion, but its the 1 in 20 occasion that people will remember.
Still... its not so bad... I usually counter this by attempting to engage a good conversation early and keep me occupied or I just drink. It might not be a foolproof system but it means I can have some fun and be less of a downer.