Scared my teen with my "work" voice

So I'm black. I have a 15 year old son who us biracial. Me and him were fighting today and saying "I'm not one of ya little friends!" And in the middle work calls. I told him to be quiet so I could answer and I uses my "work" voice while talking to them." When I turned back to hin after getting off the phone he looked like a deer in headlights and said "Who are you?! Wheres my mom?!' Honestly that cracked me tf up. He called it my white voice. I said its my work voice