What does it mean when your nipples hurt?

[Cicero]

So here's the thing, sometimes my nipples will hurt and it seems painful when my shirt is against them. Typically, the shirt would never do anything to them. I may have worn the shirt a hundred times and never experienced it, yet one day the shirt rubs against my nipples and my nipples then hurt. They even hurt when I touch them. What does it mean?

[Crazy Mad Teenager]

I get that a bit as well dunno why it kinda concerns me :o

[Naue]

It could be that you are releasing hormones at that time as the nipples are where some hormones are released from.

You might find that there is a bit of a hard lump behind the nipple, that's totally fine.

It's just a part of growing up!