A stock expression from the vocabulary of baseball slang. The 'high hard one' is a fastball pitch delivered high in or above the strike zone - an intimidating pitch because of its speed and proximity to the batter's face and head. By extension, anything frightening or painful.

when you're hungover as shit after a spending a night drunk as a skunk

A tall, rock-hard cawk.

a big fat cock
or
getting stiffed (by a big fat stiffy)

A big erect dick.

phrase. Ice hockey term for a fast rising slap-shot. Also a sexual euphemism.

.............................

getting stiffed.