Please go and get it checked out. I've just been to the hospital with mine and it is all fine, just fluid in the ducts, hopefully yours will be too. The consultant didn't say but I wonder if it's something that happens to women about 52 years old?
inverted nipples is often normal for some women, HOWEVER in your case, since this is a new finding I think that you should see a doctor. Puckering or alterations to nipple shape can be a symptom of malignancies of the breast. I think you would be wise to have this ruled out.... have you had a recent mammogram? It might pay to get one if you can - but you could discuss this with your doctor.
good luck,
let us know how you get on :)
http://www.breastcancer.org/symptoms/inflammatory_bc.jsp
Please look into inflammartory breast cancer, just to be sure.