This article is from the Piercing FAQ, by Anne Greenblatt with numerous contributions by others.
Most people experience some level of discomfort or pain during the
piercing procedure. The amount of discomfort or pain you feel is
influenced not only by the location of the piercing but by your state
of mind. When performed by an experienced piercer, most piercings
require only a second to be performed and pain is minimized.
Many people find breathing exercises helpful towards relaxation,
concentrating on breathing slowly and deeply during the entire
procedure, even while the piercer is preparing for the piercing. Many
piercers will work with your breathing pattern, either by piercing on
your exhale or on your signal. Holding your breath will cause you to
tense.
A feeling of light headedness or slight dizziness during the first 10
to 20 minutes after the piercing is not unusual. Some people feel a
rush of adrenaline and endorphins. Both sensations are the part of
body's natural chemical response to what it perceives as a sudden
injury.
Some people do react strongly enough to faint. If you feel faint
recline with your legs elevated. People who have not eaten within 6
hours of getting pierced are more likely to feel faint.
Most importantly do not feel embarrassed if you do feel lightheaded,
faint, or become nauseous. You cannot control how your body reacts and
your piercer is already familiar with and prepared to handle these
responses.
 
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