The swelling isn't quite as bad as the coldness issue. Swelling comes and goes, that's part of Penis Enlargement, it's your body's way of dealing with the stresses imposed. Fluid builds up in the tissue, then gets reabsorbed.
The cold is from lack of bloodflow. Your body, and all it's appendages-including your cock, are meant to remain at a fairly constant temperature. When just one part becomes very cold it means there is no nice, fresh, warm new blood getting to it bringing oxygen and nutrition.
In your penis blood is supplied via arteries deep in the penile tissues, blood returns via veins much, much closer to the surface. Consequently, it takes much less force to stop the blood from flowing OUT than it does to stop the blood from flowing IN.
And your lymphatic system (designed to drain excess fluid from anywhere in the body among other things)
depends mostly on the contraction of muscles to work.
This is how blood trapping, tissue swelling and fluid retention are brought about. Since your penis has doodly-squat for muscles; your HANDS must power the lymph drainage system.
I'd suggest breaking up your sessions into 15-20 minute periods and jelqing/massaging a fresh blood supply into your penis. Last thing you want is yer dick drying up and falling off like a slim jim!
Like I always say: You can't train a broke dick.