Was my reaction caused by insecurity or by having a lot of confidence?

Recently, a lady at work was told she looked nice and cute by my boss and this happened right in front of me. I was devastated because I have always been considered attractive but someone else received the compliment. Since then, I have asked quite a few people about my reaction and many have said it is because I am insecure. I don't think so; I think I reacted like that because it was a blow to my ego. Hypothetical situation: if you were a pianist and playing your piano next to another pianist and someone came along and told the other pianist how great he or she was, would that not make you upset? Isn't it true that the more confidence you have in yourself, the easier you are to become deflated? In other words, if I never thought myself attractive, I would not have become upset at another lady getting the compliment. Do you think I am right. It was not a lack of confidence that got me upset, but having confidence in myself and feeling deflated when someone else was told she was cute. What do you think?