Last Wednesday I had a small area become tender under my left bicep. 2 days later a large bruise formed. By Friday night, another not formed further down my arm closer to my elbow, it s now bruised up as well. The tenderness from where the origional pain started is now causing tenderness up to the armpit. I went to my rheumatologist today, he said he is baffled, he drew blood, and put me on prednisone, which I started tonight. He told me to call to come back in if I had any more form by Friday. I realized about an hour ago, I now have a knot that has formed on the top and another on the bottom of my forearm. Do I call tomorrow or wait a few more days with the prednisone?