It is not uncommon to hear parents talk to me about feeling disappointed about something their teenager has done. This can be about grades, a decision they have made or many other things. Sometimes the "thing" is really big and sometimes it just feels really big. Either way it is something that needs to be discussed. We often have to remind ourselves about adolescence. Teenagers don't usually do something just to disappoint parents. However, it may feel like that at times. The decision making process is just not finished yet and they make decisions that are not thought out well. They can be very impulsive and act without really thinking. Now, there are times when they are not setting out to disappoint us but they are rebelling and they often direct that at whatever they think might "get" to us. They don't really think that out so well but that is still the agenda. In those instances our best defense is to not over react. The calmer we are the more they lose the power of their action.
Whatever the agenda we need to say calm and discuss the incident with them. When they are not ready to talk take a break and then try again.
Good Luck Sherri