My spine hurts at the tip near my anus?

Coccygodynia. Coccygodynia refers to pain in the coccyx, with sharp or achy discomfort radiating into the rectal area or buttocks. Organic coccygodynia is caused by traumatic arthritis due to coccyx dislocation or fracture (from injury or childbirth). Prolongued sitting contributes to functional coccygodynia. There are of course many other causes of rectal pain (covered in earlier healthtap answers).