This treatment is being suggested on bases of the information provided. However  I would like to examine & investigate your mother 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) 1tab 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. --. Sleep on a hard bed with soft bedding. --. Keep  no pillow under the head. --. Avoid painful acts & activities. -- .Do mild exercises for the affected part. --.(for exercises,take help of a physiotherapist or visit my you tube channel 'Dr N C Gupta yoga simplified') --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 Contact your family doctor or visit nearest hospital. --Wish you a quick recovery & good health. --I hope, I have solved your problem to your satisfaction.   --Kindly rate the answer. Dr N C Gupta MS (ortho).

Agree to previous advise most importantly absolute bed rest for two to three days

It might be muscle sprain or disc problem. Consult orthopaedic dr. Use hot fomentation. Physio with IFT , USG massage will be helpful. She might benefit from Muscle relaxant and pain killers. Better to consult to get prescription because of any allergy or drug interactions.