There’s nothing wrong with getting mad, as long as you are mad about the right things. Even God is described at times in the bible as being angry, jealous and vengeful. He got mad about evil, and people who live their lives full of self gratification and indifference to others.
So get mad about immorality, hypocrisy, dishonesty, betrayal and insincerity. Getting angry usually brings about passion. Passion for the right cause is a good thing. Just make sure it drives you to being more steadfast in your determination to make good decisions and to set a good example.
And don’t take your anger out on folks who don’t deserve it.