I was going through some coins that my dad had in a jar. I found this unusual looking 1999 D penny. It appears to me that there is a D on the left side under Lincoln's portrait. I am new to looking at coin. It is not dirt, because I used acetone and a q-tip and gently wiped the area. I looked on line for this error and could not find it. Do I have a special coin or just a special imagination?