Patient: Hii have a painful lump under my bicep in my right arm very close to my elbow, i also have the same thing under my armpit. i started to feel this pain yesterday and its getting worse. i recently had a blood test and i was sure the young nurse did not do it properly as he was not sure where exactly he needed to do it and my arm went black and blue for about a month after. could this have anything to do with my pain? also the painful area under my bicep is also slightly swelling and blue. Could it be a blood clot? should i worry?