Plz add few more details of your life style in the mean you should seek help from a physio atleast to guide you for further management at times there may be a strong need for medical management, once after assesment your physiotherapist could guide you to any ortho or neuro physician that will be the easiest way for you to get rid of the problem.

Take X-Ray and check ur calcium and VitD levels and for legs start some strength exercise like cycling and walk and stretch ur leg muscle. If u have no past injury And for back u can tk physiotherapy for few days