I Have A Very Bad Pain In The Back Of

I have a very bad pain in the back of my neck on the left side that goes down my neck into my shoulder and into my arm to about my elbow. It has been persistent since this past Thursday and feels worse today. I had a very bad cold/flu last week and thought that maybe it settled in my neck but nothing is helping the pain. I've tried Tylenol, Ibuprofen, icey hot, cold packs, warm packs...nothing is helping it. I also pinched my sciatic nerve last week Tuesday but didn't think this would be related but thought I would mention it.