My mom isn't home from work yet.?? *Seriously worried!?*?

My mom had a weekend night shift, *she's a nurse* at this hospital, and she went to work at 10:00 pm, and was suppose to come back at 7 am. It's 11:48 and she isn't back! I called her cell number 5 times, and she didn't pick up. I thought of calling the hospitals number, but I lost the hospitals number! My dad, my brother, and my sister are all worried. I called my grandparents, since my mom sometimes stops there to just say hi, etc. And my grandma says she hasn't seen my mom. I would also call my three aunts, but it's unlikely my mom would go to their houses at this time. Should we call the police.? Please help!