It means you're horny or have chills.
Everyone is different. When you are young your nipples may be hard a lot of the time. As you get older your nipples tend to become hard only when you are cold, wet or sexually aroused.
Because you're horny?
Sexual stimulation is one way, and another would be that she is cold.
It could mean that you're about to come on your period
you can either lose or gain sensitivity; your nipples may or may not be hard all the time; they may get a little darker, just the nipple part. and some people are really different, so it can go anyway at all, really.
It all depends on the way your nipples were made!some are squished in and some are pointy!if your nipples are pointy it doesn't matter if they're squished in that's fine too!
Play with it using you tang by means of liking around her nipple and so fort..
Not all male mammals have nipples. I believe mice, rats, and horses are examples of mammals where the males do not have nipples. In fact, the platypus is a mammal, but it has pores and no nipples. Why this is, I do not know. I am trying to find out, but the information seems to be hard to come by.
It's from all the dirt that goes in there.After 2 days,it gets all crusty,yellow,and hard.
She's obvioulsy drank too much Dr. Pepper xP
Yes, all female raccoons have nipples.
alot of women do have inverted nipples and have always been like it but if they all of a sudden become inverted you should get this checked out by your gp as it can be a sign of breast cancer.