It could be an infection under there, but it's difficult to tell. Just go and see your gp, especially if you're worried. That's what they're there for :-)

yer i have the same thing my gp sed its nothing to worry about its just hormonal..

Im a guy and i like my nipples to stay hard.(and no im not gay as if that has anything to do with this question)and I also got them pierced.They get hardwith normal activities,
but i want them to stay hard all the time.
Can this be done ?