Painless lump and BF

mayaruth81

So about a week ago while I was doing breast massage while pumping I found a lump in my left breast, about the size of a large pea.  It's completely painless, it's solid, and I can kinda move it around when I feel it.  I try and massage it every time I nurse or pump on that side, but it never changes in size.  A blocked duct would be painful, right?  So I'm at a loss about what it could be, besides freaking out and thinking it's a tumor or something.  Have any of you had a random lump that developed while breastfeeding?  I have my "6 week" checkup on Dec.12th (that's as soon as the office could schedule it and it will have been 8 weeks postbaby for me).and I can't get in any sooner