What Causes Pain And Numbness In Fingers In A Diabetic Patient?

I have pain and numbness in my fingers worse on my left, I am diabetic and have Hyperthyroidism, a smoker, I have been a massage therapist for 16 years , my finger tips get cold and I get white spots . I suffer from leg cramps since childhood and while driving or while using my hands it becomes worse also cold makes them worst it is in both hands. Sometimes the pain is so server it wake me up at night.