If you purchased the Strength Test when it was premium, and now you just feel cheated as you could have spent those Clams on something else.
You could get be entitled to a refund, and here is what to do:
Go onto your game > tap on the squares icon at the bottom (left handside) of your game screen > tap Help & Support > you will see a Contact Us tab, tap this and send them an in-game message
TinyCo are giving refunds to players that bought the Strength Test with Clams. You can also message Matt F TinyCo via facebook on how to get a refund.