BMH

BMH is an acronym for "Banging my head". It is used most commonly for when a person is acting stupid, or it can be used if a person is brain ded.

Example 1

guy 1 : *does something idiotic*
guy 2 : BMH against a wall, bro why are you like this!?

Example 2
gal 1 : Sis, you ok over there?
gal 2 : BMH against the table I've just procastinated so hard and the deadline is in mere minutes.