Worked out last week got a sharp pain that lasted only a few seconds. now i have a pain in my chest that travels to my l arm, r side of chest and back?

See your doctor: Although this could be due to muscles strain from your work-out. With the symptoms you describe you should ensure that there is nothing that can be potentially life threatening going on, so you want to be immediately/quickly evaluated by a physician -- they may have to recommend ekg, and other tests to ensure that there is nothing life threatening, like a vascular emergency or cardiac issue.