Sometimes you will have feelings that you may find kind of "ugly": an uncharitable grudge, taking bigoted offense at something, etc.
Those feelings are real too. They don't make you evil, but they may alert you to areas where you need to grow or change.
Sometimes a feeling that we KNOW is unjustified but still feel intensely is actually a flag to let you know, "hey, there is something here you need to deal with."
Emotions aren't good or bad. The question is what you do with them.