Undecided Question

Why do Blacks discriminate against each other?

I'm a 15 year old high school school student and i happen to be a darker skinned african american. I don't know if its only this big with blacks but it seems to me that the darker you are the more hell you catch from anyone lighter than you. It's the lighter against the dark and the dark against the darker. Im not saying that every african american is against one another. I just simply want a different view from everyone, i dont care what race or color you are, and to all darker african americans i want to know if you experience this or have experiened it. If yes how has(does) it made you feel?