I found a 1957 pennie while looking at my Wheats. The 5 is fill in. I put it on Ebay sold it for $2.00 plus S&H. Did i get riped off?
Probably the product of a die chip (piece of the die chipped off). Nothing special except to someone who collects that type of stuff. Minor error. If you got $2 for it IMO you did well.
I echo my predecessors' comments. You did okay if you can replace the coin for less than you sold it for. Clinker