That is not a small date. It is a large date. There are no P mint mark Cents so it is impossible for a D to be over a P.. It Could be a Die Chip or damage. Before I am corrected.. There is one year and only one year that the Philadelphia Mint used the P Mint Mark and that was in 2017. But I tell you again that there was no P mint mark used previous to 2017 on a Cent.
Other coins have P mintmarks. Dollar coins since 1979. Nickels, dimes, quarters and halves since 1980. But not pennies. Yes in 2017 they did it as a sort of 225th anniversary tribute to the mint? But otherwise pennies never carry a P mint mark. I wonder if there is some new You Tube video going around, as all of a sudden I see 3 posts about P over D or D over P mintmarks. I don't believe this is a modern issue. Were there any newer than 1955? Have there been any in the last 65 years?