Re: Medela sizing
Here is a guide on the Medela website. In my experience I had to buy a couple of different sizes and try them out because my breast shape didn't particularly look like any of the pictures. In the end I had to use two different sizes for my two different breasts. The overall goal is to have all of your nipple pulled into the narrow part of the flange, without rubbing/pain, and with as little of your non-nipple skin pulled in as possible. If the nipple is rubbing with the small, then it is probably too small.
I have never tried their Comfort Breastshield, maybe it would work for you?
My little man was born 12/17/2010.
Baby girl was born 4/30/2014.