Does anyone know if this is something to worry about. As I was feeding her last night I felt a lump between her nipple and armpit, and it is about 1cm x .5cm in size. It moves when I push it and it feels pretty hard. I do know that lumps under the nipples is common at birth but does anyone know anything about ones that appear later?

I tried feeling it this morning when she was awake and she pushed my hands away which indicates she doesn't like it but didn't cry in pain.

Any help would be greatly appreciated. I work full time at the moment so I can't get her into the drs until friday.