I sweat a lot more than i used to and i have very cold feet and hands if i rest and lay in the bed, especially at nights.what is the cause of it?

Cold sensation: This could be caused by a bevy of things, such as nerve issues, connective tissue diseases, poor circulation. If there is pain, skin color change, weakness, or cramping at rest please seek professional help.

Many possibilities: You may have a neurologic or a vascular problem, but it could be other problems. Have it evaluated by a professional and get the proper treatment.