[ Singles & Dating ] Open Question : Should I be angry or jealous?

My boyfriend complimented this girl that he supposedly "used" to like. He told her that she was sexy and cute and more . I'm not the jealous type of person but knowing that he used to like this girl makes me insecure. Just to state, we are only about 14. How should I deal with this? And no I do not want to confront him about this in any way.