I agree with what everyone has said. I'm a DD and had mine done in december of last year. Tight clothes usually aren't a good idea around piercings, but I think because bras conform rather thatn constrict the nipples, they aren't the same problem. Tight jeans just push on a navel piercing, a bra will cradle the piercing.
I think wearing a bra or tight shirt for the first few days/week is a really good idea. The pain seems to subside pretty quickly with nipple piercings, at least with mine.
Good luck, if you have it done, they are really great piercings.
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