What Causes Painful Bunch Of Red Dots On Elbow?

im 20 years old and woke up this morning with pain on my elbow and with a bunch of tiny small red dots , it hurts when i just bend my elbow. I had gone to the emergency room this morning the doctor did take x-rays to make sure there wasn't any fluids in my elbow there wasn't and they did take my blood since i told them I'm anemic i came back as a 12 blood , im sure what that means but they said my blood fine. but they could not tell me why this was happening to me and they said if it gets worst come back. i just want to know whats happening .