I am at a disadvantage here since I can't see your foot or the X rays. If you have a posterior spur in the Achilles tendon, it is not usually recommended to have an injection there. Obviously there can be exceptions and that is why this is a difficult call. Other things that can be done include heel lifts, ultrasound, night splints, ice masssage, or immobilization are some.
Only if all conservative treatments fail do I consider surgery. You discuss your options with your doctor.