I don't even
A phrase originating on the internet used to express complete and utter shock or not knowing what to say
Example:
Person 1 : OH MY GOD A CAT IS PULLING A WATERMELON OUT OF A SPACESHIP
You: OMG WHUT I DON'T EVEN
Person 1 : OH MY GOD A CAT IS PULLING A WATERMELON OUT OF A SPACESHIP
You: OMG WHUT I DON'T EVEN