How To Treat A Lump On The Spine?

Hello Dr. I am 16 years old, about 6 2 , weigh about 220lbs. During gym when doing crunches I noticed a pain on the bottom of my spine, a small hard round lump was there. I dismissed this as nothing. 2-4 months later(now) I just found a hole a few inches below the hard lump, which I think has grown in the last week. Wateryish blood sometimes comes out when I excrete stool and I am worried. ANY AND ALL HELP IS APPRECIATED. Thank you.