Dreaming that you got a piercing can represent:
Compromising your integrity or your own personal boundaries (where your skin represents your personal boundaries)
The idea of tending to sacrifice your integrity or health for the sake of appearances or frivolity
The idea of compensating for feeling not good enough, not self-expressive enough, or wanting to feel different or better than others, etc.
Believe in yourself and who you are, just the way you are.