Querulous- grumbling; grumpy

(adj.)

Sentence #1

Abigail was in a querulous mood when her parents said no to her Friday night plans.

Sentence #2

The querulous student got a bad participation grade every class because he was always in too bad of a mood to ever raise his hand.

Antonyms:

complaining, fretful, dissatisfied

Synonyms:

cheerful, easy-going, happy
Snow White Why Grumpy you do care