I'm not 17 anymore. I still have some of the same sort of anger, but I have a sense of humor about it... a sense of being constructive with that anger.

This quote means that although the speaker is no longer seventeen years old, they still feel angry at times. However, they now have a sense of humor about it and feel more able to do something constructive with that anger. This suggests that they may have a better ability to manage their emotions and use their anger in a productive way.