惊慌失措

to lose one's head out of fear (idiom)

to startle / to be frightened / to be scared / alarm

to panic / to be alarmed

to get panicky / to lose one's head / (coll.) (after 得) unbearably / terribly

to lose / to miss / to fail

to be at a loss

to handle / to manage / to put in order / to arrange / to administer / to execute / to take action on / to plan