You have to consult a doctor.
But for temporary take some ginger juice(3-5 ml) with tulsi(Ocimum Sanctum) leaves, 2-3 times a day. drink Hot water throughout a day. take rest. Fasting will help you to cure fever
and other symptoms if possible do it. during fast drink only hot water.
For your Tailbone consult nearest orthopedic Doctor, if needed he will take x-ray and diagnose what is problem, once diagnosed you can take Ayurveda treatment for that also.