how old are you?

Discharges of nipples are not usually harmful and doesn't mean anything that is seriously wrong. Actually, most women can squeeze some discharges out of their nipples, especially when they have children once...This may be whitish or may be yellow-green in color or almost black.

On the other hand, nipple discharge can be a symptom of breast cancer, particularly if it is bloodstained....That is why you should discuss this nipples discharges with your doctor...If you are a man, you should see your doctor straight away, because the usual cause is a tumor and you will be needing a treatment.

She doesn't have any discharge.

As for the original poster:
Inverted nipples are totally normal, and it is also normal for them to become uninverted.