dd is 11 weeks and bfs really well. however, one boob gets really full and heavy while the other seems to stay the same. milk supply seems to be the same from each and I'm pretty sure that she "uses" both of them equally.the difference in size is actually really noticable if she hasnt fed for a few hours though!is this normal and any tips on how i could even them up a bit?have tried expressing but doesnt seem to help...