Hello. I have a collapsed left shoulder and torn rotator cuff, which occurred as a result of Lupus and the high dosages of prednisone I was prescribed to treat it. Four days ago my left arm and right leg began swelling, and my rheumatologist ordered an ultrasound yesterday to check for potential blood clots. All was normal, but my right subclavicle vein was 100 cm/s while my left was only 20 cm/s. Suddenly, about 30 minutes ago, a pronounced, protruding blue vein appeared across my left chest and shoulder. What steps should I take?