The Italian word nervoso doesn’t mean nervous when describing someone’s behavior. It can mean:
tense
edgy
irritable
crotchety
If an Italian asks why you are nervoso/a, it doesn’t mean you’re nervous but it is likely that you are tense and edgy.
Quando Marianna ritorna a casa dopo il lavoro, rimane sempre nervosa e distratta; pensiamo che abbia un capo diffici…