Found this gem. Crack in the die and the mint is stamped on the date, plus 3 dots on the trim near the liberty . What do you think about it?
Lools like a Lamination Crack issue. It affected the date. Itbis definitely not a mint mark on the date. IMHO
Your coin is a 1930-P cent with a lamination error. I suspect that it has been cleaned. the marks on the edge is post mint damage. Like paddyman98 said the date has been effected by the lamination http://www.error-ref.com/retained-lamination/.