What do I do? And how do I tell my dad?!?

I went to wrestling practice as usual and I put my phone in my locker as usual and locked it. I thought everything was alright didn't second guess myself. But then after practice my locker was open and my cell phone was gone!!!!!!!!!!!!! I tried calling it and texing it but no answer. I have heard of other people opening lockers and taking phones before, but I thought it would never happen to me. I guess I was wrong. But now how do I tell my dad I lost it? HELP ME PLEASE I AM DESPRET!!!!!!!!!!!!!!!!!!!!!!!!!!!!!