I know you not laughing - The 5 words that mean you're the dumbest person in the room

The 5 words that mean you're the dumbest person in the room and you know it.

My buddy laughed at my failed attempt to cook. 'I know you not laughing.'

My neighbor cackled at my awkward attempt to sing. 'I know you not laughing.'

My dog laughed at my face when I tripped. 'I know you not laughing.'