I gave up breastfeeding after 2 weeks cos I don''t think my latching on was right and I ended up with a blister that popped and got infected(I did express for another 1 week but it kept making DD sick as it had blood in it and probably pussfrom the infected bit, it was horrible) 7 weeks laterI still have milk and now I have a hard lump in one side just next to my nipple - it's about the size of a large marble. Is this normal?