mullygrub
At our house, mullygrubbing always meant feeling sorry for oneself, being in a blue funk, morose...a GrubWort, on the other hand, is a very dirty little kid, usually with sand/ dirt/food, etc. stuck to his face and hands
She had been mullygrubbing all day, complaining and scowling. 
The little GrubWort left tracks all over the kitchen floor.