What Causes Soreness And Pain In Tailbone After Injection?

i had an injection in my on each side of my buttocks when i walked out of the doctors office i could hardly walk that week my tailbone and my butt were sore only when i sat down i went back for an x-ray and did not show anything wrong with my tailbone. did i have nerve damage done from the shots. it has been three months .i have been to therepy and actupunture and i exercise all the time thanks i am 58 years old and in good health