Can a tailbone that is too long and too close to the anus damage the anus/sphincter? i think mine is dangerously close. and if so, how can it be cured?

Coccyx: The coccyx, the cartilaginous structure at the end of the sacrum can theoretically impede the passage of stool through the rectum and may require surgical removal. However I would consider this a rare circumstance. If you have concerns or if having difficulty passing stool,consult a proctologist or a colorectal surgeon for evaluation and advice.

Irregularity: Before working about damage from a hypothetical situation, see a General Physician for a complete physical examination, probably routine lab tests, and possibly le imaging. If an anatomic irregularity is found, appropriate treatment choices can then be discussed.