If you go to the site Rick posted above they have repunched mintmarks for this date. See if one of the pics match what you are seeing. Your second pic doesn't look like the first.
Wiley, I do not believe it is a RPM. There is in the photo the appearance of a vertical bar to the left of the mm, but as bold as it appears, there would have to be a portion of the curved front inside the original D , and there is not. With the graininess of the photo, I can;t tell if it is discoloration or some MDD. Jim