I used to, (well I still do to some extent) but it is probably different for everyone. Nervous expression can be expressed differently at different times. It was a major problem for me when I was in college labs -- disecting, measuring liquids, holding test tubes with tongs over a flame, ...etc. People used to ask me if I was on drugs or an alcoholic, because I'd get the shakes so bad.
It was worse when I was being watched and tested on the spot - or called up to the board to work out a problem (believe it or not, college professors still call people up to the board like high school teachers, lol). My legs and body would quake, and I would try so hard to hold the marker and write without making a mess of things. It did get better the more familar I was with the people. Routine and familarity helps me a lot. The problem was, every 4 months my routine changed and had to start over ... the shakes would come back as bad as they were the first days of the previous semseter... but would eventually calm down.
Like I said, it is probably different for everyone. New situations, being judged or evaluated, meeting new people, having to talk on the spot ... I believe this is due to a surge of dopamine in these kinds of situations. Dopamine is the neurotransmitter that acts on the sympathetic nervous system, which increases your heart rate and blood pressure -- and can trigger the fight or flight response (give you the shakes); ptsd sufferers usually are highly avoidant of situations that trigger this response unless we educate ourselves and can understand why our body is doing what it is doing. Knowing kinda makes it a little less ... troublesome? annoying?
To counteract these responses I had to find acetylcholine triggers (this acts on the parasympathetic nervous system). This will decrease the heart rate, slow breathing ... the relaxation response. I use my senses -- pleasent aromas (I have a tissue in my pocket with a certain aroma oil on it I can pretend to wipe my nose and take a few breaths of it) ... can use imagery in your mind of certain places you feel most relaxed in (I like the desert because it seems quieter) ... use an mp3 player with music you enjoy ... just any senses you can utilize to help you calm your nerves.
It does take practice. For me, routine and familiarity helps the most.
There is also something called 'Rescue Remedy'. They come in drops for under your tongue, or in losenge form; can help relieve anxiety to a point. You can find them at a drug store, or Amazon carries them too.
Hope you find any of this helpful. You are not by yourself with this issue.
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