Is this a repunched mintmark or machine doubling? Or something else? Even if it's only worth $0.01 (well, $0.017 when you take into account its copper value) I'm still keeping it because I'm proud I even noticed it!
I would say it looks to be this die. http://www.ngccoin.com/coin-varieties/lincoln-cents/1960-d-d-large-date-1c-vp-002-3956/ You will want a second opinion because those kind of things are not my strong point but I would say it is.