You are definitely not overreacting and your feelings are totally understandable. As one poster said he may not know you have been charged....On the other hand, maybe he does...If he did/does know he should have spoken to you about it first and told you he was going to put it through to the system. Surely he would know (should know at least) that it would cause some negative feelings? You will need to speak about it in order to get back some of the trust it feels like you have lost.

Although a very different scenario it reminds the time my friend once had a chimney fire. She was worried it might get out of control but felt it would be okay. A neighbor offered to call the fire brigade for her to which she accepted just to be on the safe side. They came out and in the end actually didn't have to do much at all and the fire died out on its own.... My friend ended up getting a bill for $500 afterward though...She understands the need to charge and the fee but the financial side of it didn't factor into things at the time of the fire so somehow she feels like she was the one that got burnt...She now swears she will never ring the fire brigade again unless the house is full blown burning down.