Wrap it with a thermometer. It probably is but still good to eat but not to incubate. Just let it thaw slowly in the fridge if you plan on using it soon. Otherwise I move them directly from the frozen coop to the freezer till I want to use them.
Maybe try spinning it like a top? I know you can spin a hard boiled egg, but a fresh egg will wobble and not spin very well. I bet a frozen egg would spin like a hard boiled egg.