perder a cabeça angolul

lose one's cool▼(to lose one's temper)
verb
[UK: luːz wʌnz kuːl] [US: ˈluːz wʌnz ˈkuːl]

lose one's head▼(behave irrationally or lose self-control)
verb
[UK: luːz wʌnz hed] [US: ˈluːz wʌnz ˈhed]