Possible skin cancer? (Photo)

I am a 22. A year ago I found something that was similar to a wart but not quite the same. Its a scab & it penetrates deep down. The scab comes & goes. I also have a hard bump on my leg that is slightly darker than my skin & sticks up a little. It has been on my leg for a few years now. I recently found a hard lump on my back by my shoulder blade about the same color as my skin. It feels deep down like a cyst but hard. Anything to be concerned about?