If my skin is turning blue, is this emphysema?

Heart, lung or other. If your lips and nail beds turn blue, you may be having problems getting enough oxygen from your lungs, or blood circulated properly. If it is one limb that is turning blue, then ou may have a problem with the circulation to that limb. Either way, if this is suddenly new, you need medical attention immediately.
Not necessarily. Blue discoloration of skin in emphysema is generally restricted to the fingers, toes and perhaps the lips. In very late stages of the disease it may be more extensive. It usually signifies that oxygen level is very low. Blue discoloration of the skin can also occur with some medications (amiodorone, a heart medication) , with chronic ingestion of colloidal silver (argyria) or gold (chrysiasis).
Possibly... A blue color to the skin is called cyanosis. It can also develop in the nailbeds and mouth and nose. It means that there is decreased oxygen in the tissues and it can be caused by many, many diseases, including empysema. If present, it needs to be evaluated asap, in the er, as it can be a sign of life-threatening disorders.