I have a pinched nerve in my trapezius. what can i do to? and how long would it take to heal? the pain spreads to my neck, upper & lower back & arms.

Depends: It is a little unusual to have a "pinched nerve in my trapezius" as you put it. Pinched nerves in the neck are fairly common, or muscular injuries to the trapezius also. I would encourage you to be seen if it does not get better soon.

Cervical traction: You could take some ibuprofen for a few days to help with the inflammation and pain. However, that is not a good long term solution as it can cause problems such as stomach ulcers etc. Get your doctor to prescribe physical therapy, particularly cervical traction. That can help a good bit with this kind of pain.