lose (someone's) head over nothing

Translations
терять голову из-за пустяков
She tends to lose her head over nothing when she's stressed.
Она склонна терять голову из-за пустяков, когда она в стрессе.
Definitions
To become extremely upset, panicked, or irrational about something that is not important or does not warrant such a strong reaction.
Words
head

noun
голова
nothing

noun
ничто
lose

verb
терять