Female nipples usually don't enlarge much at all since they're fully developed already.
But if you have snug rings in that like to stand at attention, then the constriction is probably causing your nipples to enlarge sideways...which could also explain your enlarged holes.
You really should have your jewelry analyzed by your piercer...or a few piercers to get a better sampling of opinions to choose from...if you have a pic, send it to me, I'll give you an opinion too.
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Semi-retired Stay-home-dad
Still teaching classes here and there...
www.propiercing.com