You'd probably do better by putting a little more info in your title, to indicate we're discussing medieval English pennies- and also by posting to the World Coins forum. Not that there's anything wrong with posting these in Coin Chat, which is a general category, but do know that these forums are US-based and so a lot of the discussion is going to be primarily about US coins.
I don't know how they tell Henry from John, since they both said HENRICVS. Here is my John penny. It was found in the Gisors Hoard in France.