hearing problems??

i don't think my baby can hear. he's three weeks old today yay. but over time i realized he won't react to something unless its in eye sight. I have put on my alarm which is beyond loud and annoying. no reaction. I've tried yelling, clapping, and snapping by his ears and nothing at all. zero reaction. i called and the nurse said she'd call me back because the pediatrician might want me to go to some other testing place. im really freaking out. has anyone dealt with this and it been totally fine?