I am a new mother of a 3 week old baby. Breastfeeding has been going really well up until yesterday. I have noticed a pain that comes and goes deep in my left breast. I did try to pump for the first time yesterday, so I don't know if this is something that I did trying to pump or could it be yeast or clogged milk duct? I could use some advice...I really enjoy breastfeeding but now I am paranoid that something is wrong!