This condition is called coccydynia commonly due to fall on your buttocks. Ligaments around the tail bone are injured. Sometimes the bone itself can become angulated. X-ray will help to rule out any bony injury
Next Steps
Conservatively managed with physiotherapy, exercises & modification of sitting using wedge cushion & sacral pillow. It will resolve over a period of time. In severe resistant cases injection procedures around the coccyx (ganglion impar block) will help to control the pain. Hope this helps you.
Health Tips
Prolonged sitting & driving will aggravate the pain