pettishadjective
/ˈpet.ɪʃ//ˈpet̬.ɪʃ/showing anger and behaving impatiently, especially about things that are not very important:
I felt ashamed at my pettish resentment.
pettishly
adverb uk/ˈpet.ɪʃ.li//ˈpet̬.ɪʃ.li/
“The key's stuck and won’t move,” she said pettishly.