Dear JanRose, Without physical examination, ability ask questions etc. it is difficult to advise you as to what this pain could be. It is best to discuss with your doctor, who can evaluate.
I have been having the same problem for about a year. In my armpit near my breast. There are no lumps and I had a MAMO done the results was neg. When I take tylenol the pain goes a way but after 8 hours or less the pain is back. Plus I am sick of taking tylenol. I'm 35 years old and also suffer from carpel tunnel syndrome. I have been praying that the pain will just GO AWAY. I have no family history of cancer. If anyone out that can help, Please! give me some advice on what to do.
I have had residual pain from my BC lumpectomy surgery in Dec '05. But the tissue tenderness is spreading outward further from the scar area where it started. I posted another question about this today so we'll see what happens.
A related discussion, armpit pain after breast removal