One should have a table top bed with soft bedding on it but not more than 3" in thickness. Lie in any postire that is comfortable. This treatment is being suggested on bases of the information provided. However I would like to examine & investigate you  in detail. Control  Hypertension, Diabetes or any other metabolic disorder, if there is  any. Any way it may be tried, --. Dolokind Plus (Mankind) [Aceclofenac100 mg +Paracetamol 350 mg] 1 tab. OD & SOS. X 5 days. --. Caldikind plus  (Mankind) 1 tab OD x 10 days. (You may need help of your local doctor to get these medicines.) --. Fomentation with warm water. Let the part not be exposed to cold. --. Use no pillow under the head. --. Avoid painful acts & activities. -- .Do mild exercises for  back and hips and knees and ankles and feet. --.(Take help of a  physiotherapist). --Do not ignore, let it not become beginning of a major problem. --Do ask for a detailed treatment plan. Kindly make sure, there is no allergy to any of these medicines. --For emergency treatment visit nearest hospital. --Wish you a quick recovery & good health. --I hope, I have solved your problem to your satisfaction.  Dr N C Gupta MS (ortho)

What you need is a firm mattress which suits your body depending on how obese you are. It is a bit of trial and error and you might have to spend some money. Meet a physiotherapist for posture maintenance and core strengthening exercises