White lump on nipple...

For the last two (or three - gasp) months, I've had a white lump on one of my nipples. It's a tiny bit smaller than this smilie :redface: but is white. When I put pressure around it, it whitens a bit more. If I'm in a warm shower, it tends to disappear a bit (the whiteness) and kinda disappears into the rest of my nipple but when I'm cold, it forms a distinct lump on the end of my nipple (well, a bit to the left of centre).

I haven't breastfed for about 5 months so am ruling out a mastitussy thing (plus I'm not sick). It can be itchy sometimes but I think that's just because I fuss with it and my nipples are a bit sensitive.

I've been meaning to ask my midwife but usually forget. I will try to remember again next week at my 31 week visit.

I'm not too worried, just wondering if anyone knows what it might be?

it sounds like it might be a blocked duct i have had something similar this time and my youngest is 5 now so have not bf in years.