Browncurtains, I'm sorry you're going through this hard time.
In answer to your question, there's more than one kind of depression. Some depression is sorrowful; some depression is anxious and agitated; and some depression is rageful. Some depressed people lose their appetites and can't sleep. Others want to eat and sleep way too much.
So just because you don't think of yourself as feeling sad, it doesn't mean you couldn't have depression.
It's normal for teenagers to have some intense emotions, but when you want to kill yourself or if you feel violent toward others, it's really time to seek some help. It sounds as though you already know something isn't quite right with the way your emotions carry you away. Which shows self-awareness. It sounds like you're ready to accept help if you can just find it.
Can you tell either of your parents that you've been feeling depressed? Or another adult relative or a teacher or school counselor? With some counseling and support, people can and do recover from episodes of depression.
I wish you the very best of luck. Please come back and tell us how you're doing. People here can offer you support and understanding.