What Causes Numbness In Feet And Hips?

i am 66 years old lady and have been suffering from numbness which started from my feet but has now reached upto my buttock area. earlier the area was numb only when i was walking but now it gets numb even while resting and the condition is extremely painful. i also get severe hot cold tingling sensations. also i have lost my sense of balance. i am not diabetic .kindly advise what course of treatmenet should i follow or which specialists to consult as my t/t till now has not yielded any alleviation of my problem. in addition for past two months i have also been coughing and no medicine from a local doctor seems to be helping.