Hello Just Wondering About My Feet....and Toes....they Have Been Ice

Hello just wondering about my feet....and toes....they have been ice cold for weeks and now the entire bottom of my feet are yellowish. Even greenish in color....I'm worried that maybe gangrene has started...if so what should I do.

I am 39 years old male ......non smoker...about 20 pounds over weight for my height. But my feet really really are cold and my legs seem so heavy....