Hello- by FAR, the most common reason for nipple pain in a 10 year old is the beginning of a healthy, normal breast bud. The inversion is most likely to be insignificant. I understand and sympathize with your worry, I truly do. It makes sense to ask her pediatrician to take a look on Monday morning, but you can rest easy until then. Diseases of the breast in this age group are so incredibly, phenomenally rare, and she is at just the right age for the beginnings of a breast bud, which could certainly cause exactly what you describe. The inversion may be a temporary change resulting from the beginnings of the growth, or may have been present but not visible when the chest was flat.
For your daughter's sake, the best thing you can do is to tell her she is normal, she is fine, and to be certain of that, you will check it out with her doctor. Your calm is important right now. Very. If this does in fact turn out to be something worrisome (extremely unlikely) she will need your calmness, and when it turns out to be the beginnings of a long process of puberty, she will need it just the same. I would go look one more time (I know you have both been looking a lot, trying to figure out what is going on), tell her the doctor on the computer said what she has is FINE, I am SURE, and tell her she is healthy. The pain will go away. We want her to feel confident and comfortable about her chest, right! Sorry if this offends you, I do not at all intend it that way- I completely understand your situation and I have been there! I feel so confident this is going to be okay I just don't want either of you to spend the rest of the weekend worrying. Anyway, since I cannot be there to see it, take her in on Monday to be seen, but after this one last look when you tell her she is OK, try not to focus on it anymore until that visit, if you can.
I wish you and your daughter all the best. This, too, shall pass!!!!!
Edited by Mom of three, MD on 7/18/2010 at 1:17 AM EST