firstly calm down. maybe his baterry went down, there is no reason to panic... athough i dont know how much time passed from his last call. if he dont call for day or two, call him and ask what happened

It depends on how long he hasn't called. If its been awhile like a few days or a week you should check with his family and friends to see if he's okay. If he is then don't do anything when he wants to talk to you he will. Do something to pass the time and don't call him go out and have fun without him, because he's not out worrying about you not calling.