My chemo for breast cancer ended September 2009. Since that ...

My chemo for breast cancer ended September 2009. Since that time, I have pain in my left arm that appears to be getting worse, and it is more prevalent during my sleep time. I've have lost most of the strength in my left arm. Note: I did receive chemo in my left arm during the time my port was not working, and during one of my medical appointment a nurse hit a sensitive nerve in my left arm that caused a lot of pain. I wish I had an idea what the origin of the pain. I have informed by doctor of the pain which hasn’t generated any concern.