Please stop smoking immediately. My father just passed away on Jan. 1st, 2011. He didn't quit smoking right away, and he went straight to severe COPD in a short time. If you stop right away, you have a chance at staying a mild stage of the disease. Living with severe COPD made the life he had left, HELL. It was a labor to do anything, mostly just to breathe was a labor. I tell you this, I'm devistated, and begged him for years to quit smoking. It seems the last couple years of his condition worsened in a flash.
The only way to slow down the progression of the disease is to stop smoking. After quitting for awhile the lungs may regenerate themselves to some degree. I am one year younger than you, doc told me if I did not quit smoking I would not live to draw retirement. I quit.