What are these small hard bumps under my skin?

[BitConfused2773]

I am a teenager who has had some odd bumps under my skin for awhile and I am gradually getting new ones. They are clustered in my fingers and the outside of my ankle bone. They seem to be completely solid and can move around under the skin. They don't hurt or anything, and they have no evidence of how they got there, like a bug bite or anything. Through my skin, I can vaguely tell they are a white color. They almost seem like white beads under my skin. In my fingers, there is one that originally was under the callus of my writing hand on my middle finger and has gradually moved downward. I thought they might be cysts but they don't really fit the description. I am worried I might have some sort of skin cancer. Please help!