When Teens makes mistakes

Often you wonder whether anything you say sinks in and when it doesn't you feel horribly depressed.  Where did I go wrong? ..... like today.....

I often know that my teen tries to manipulate a situation to suit his needs but today his needs became more important than the safety and comfort of his latest female friend.  It started out with a dinner request and I said yes, although I was not here, his father entertained the young lady at the table while my 14 year old behaved in a disrespectful manner to his family while helping himself first.  He then went on to turn down a request we had to take the young lady home because he said her mother would pick her up at the mall at 8 p.m.  I called him on his cell phone at that time only to be told that he was heading home...... when we tried to call back his phone was off.  I had to find him and bring him home not realizing that the girl he was with was the same one who came to dinner but he did not introduce her, but waved her off as he followed me out the door to go home.  Angry and disappointment come to mind but more so a deep seated dread that maybe I didn't teach him well and maybe others do not hold any importance...... he is sitting at the kitchen table with phone in hand now trying to call her to see if she got home O.K because the realization that she is not home yet at almost 9:30 is just too much for him to digest...... that conscience will be his saving grace when he finally grows up to become a man.  Right now, I am trying to get him to do the right thing without losing my cool...