That feeling after you've done something really stupid or badly fucked something up where you are bracing for the well-deserved, unpleasant and unavoidable consequences of your actions that are about to hit you.
i.
e. your boss is gonna give you a verbal beatdown or
fire you, because you didn't lock up after closing and the shop got robbed, or your
partner is going to chew you out or possibly murder you because you bet the rent on that 5-part parley that didn't
hit.
Sam just found out that the boss knows he's the
one who left the keys in the work
truck that got stolen last night, and that the boss wants him in his office as soon as he gets back to the
yard, he's preparing for a railing.