If you see something, which I don't, it's probably a plating issue such as a bubble or blister which is common in Copper plated Zinc Cents. There are no Overdate Lincoln Cents known. A cent without a mint mark was minted at the Philadelphia Mint. Yours is not a S - San Francisco Mint.
Not that perfect I want to share this webpage with you - https://en.wikipedia.org/wiki/Pareidolia Quote - "Pareidolia - is a psychological phenomenon involving a stimulus (an image or a sound) wherein the mind perceives a familiar pattern of something where none actually exists." closed quote