Hello! I am a 19 year old girl and have discovered a hard lump (best way to describe it would be bone hard) on the lower left side of my back. I am lactose intolerant and was in a car crash last year but was cleared by a doctor. I was just wondering what this is and what corse of action (or lack thereof) I could take? I was thinking a possible Epidermoid or sebaceous cyst or a tumor or a lipoma. Just ideas I m no doctor or surgeon obviously haha. So I would love some amount of guidance. Thank you so very much!