Swelling.....Can you help?

I have noticed (and become uneased) by one of my nipples swelling during the day. It gets rather large and there is no definition between it and the areola, what i would like to know is - is this normal? Or does anyone know what causes it? I go back to the midwife in early March so will ask her then, but wondered if anyone could offer any advice in the meantime....
It doesn't hurt or anything, just the normal itching and loss of fluid! Ever so attractive this pregnancy lark isn't it?!?!?! LOL!

[Modified by: AprilH on 11 February 2008 18:24:02 ]