Flan lamination flaw, yes, but double strike no - you mean instead clashed dies, thus imparting part of Viccy's face to the reverse die and then all subsequently struck coins.
And the vertical bit by her nose is a corresponding clash from the edge of the shield on the reverse. I suspect the misformed G is also the result of the clash with whatever letter from the reverse legend corresponds with it. All interesting, but nothing really abnormal or a genuine error here as die clashes are very common in the Victorian series and lamination occurs as a result of trapped gas bubbles in the metal mix for the blanks.