I am expressing every few days (sometimes 2 or 3 days in a row, others one day express, one day not) trying to build up a freezer stock for LO for when I return to work in March. I didn't think anything of it to begin with as just thought it was coincidental but I think there is a pattern now............I think expressing is creating a reoccuring blocked milk duct in my left breast. It is fine and not blocked when just feeding but when I go to express - a few hours later I'm finding the same sore blocked duct. Anyone else get this? I'm using an electric pump and pumping till the milk flow stops plus 2 mins. Is it because I'm not regular or routined in pumping because this isn't always possible with day to day activities!?