It's probably just a die chip, but could you take a photo of an individual coin clearly showing the area in question?
Cracks on the forehead and in the hair are prevalent on the 2014 P as well as cracks and die chips on the upper left side of the shield on the reverse. It is possible to have a die chip on the forehead also. This is true of the reverse of all the shield reverse's. As stated above, a close up photo would really help. Also there can be a die crack on the lower left of the reverse shield to look for. I have yet to see much wrong with the 2014D yet.
The small nub on the top of the shield is a die chip, the result of a die crack that runs very close to the top edge of the shield. These are very common on all of the new Shield cents and especially from the Philadelphia mint. The die cracks are usually very thin and I've seen few that are big and advanced.
