Also, I just started my period today (and the lump
appeared today). Could it be that hormones caused the lump
? Though that does not explain why a lump would appear now, all of a sudden. In addition, I've been to a doctor in the past year because I had some unusual breast pain (that his since gone away). There was an ultrasound done, but no problems were found.
I have no clue what might be causing it. I have read that it could be a number of things.