Hello Sir, My Name Is Ashish I Have A Pain

hello sir, my name is Ashish i have a pain in tailbone at the end of spinal cord, but it is worst after SEX or MASTURBATION.

i am using DONUT PILLOW to sit for long hrs but what is the permanent solution. i consult the top rated doctors but some fooled me by just giving vitamin D tabs and some gave me exercises i did that to for 5 to 6 months but there is no result