I am a 28yr. old female. In Jan. 2007, I found a lump in my right breast. After about 2 weeks it was gone. Since that time I have had pain behind the right breast. At first the pain would come and go, now it is almost a constant. The pain will radiate up into my collar bone area and down my right arm. I will have "bad" weeks where I am very tired and not much energy along with the pain. I went to the doc Oct. 2007. I've had a breast ultrasound and bloodwork and all seems fine. This month I went for a chest-xray and am scheduled for a CAT Scan. In the meantime I am worried and wondering what this could be. I am wondering if the lump I found was just a coincedence, since the pain seems to be inside, behind my breast. It is very hard to describe the pain, but it is not like a pulled muscle or anything. Any input would be helpful. Thanks!