Bruise On Spine Which Is Changing Color, Pale, Throat Pain, Bump Between Jaw Bone And Neck. Treatment?

I have a bruise on my spine. It's about 7 inches long. My mom first noticed it when she was rubbing my back about a month ago. At that time, it was blue and green. Now it is dark red, purple, blue, brown, and slightly black. It randomly appeared, and I have no idea what its from. my back generally hurts, but not where the bruise is. I also woke up a few days ago with a quarter sized bruise on my arm. It's a light brown, and yellow. If the following information helps, I'm always pale, my throat hurts, I have a bump between my jaw bone, and top of neck (moves around, and is hard. Hurts if I fiddle with it a lot; has been like this for about 4 years), and head pain. My joints also hurt a lot of the time, and badly. I'm 13 years old , as well. Thank you.