Here are some links you may find helpful:
http://www.lalecheleague.org/llleade...yjun89p35.html
http://www.motherandchildhealth.com/.../inverted.html
one of my nipples was kind of flat and so I had to work with my daughter when she was really young to get her to latch right. What I would do was make a "breast sandwhich" squeezing in the direction of the babies mouth (e.g. if she is cradle hold, you want to squeeze from 10 and 2 o'clock and if she is in football hold from 6 and 12 o clock). This helped her to get more of my nipple in her mouth. How old is your baby? Is she gaining? It might not have ANYTHING to do with your breasts or your supply. My daughter went through a phase of pushing into my breasts and to this day she slaps them when she nurses, but I have never had a supply issue. It is possible that she is more efficient at getting it out now and that 4 -8 minutes per side is enough. My daughter started out nursing for an hour and a half on each breast and now she is down to no more than 8 minutes per side (she is 9 months). Did you have a problem with oversupply? If your flow slows down (that isn't to say you have less milk!) she may be getting frustrated that it doesn't come down fast enough. In that case, you can also squeeze your breast. It will help the milk come out a little faster and give her the encouragement to keep going! Don't give up. Breastfeeding is one of the hardest things I have ever done because they are changing so fast and just when something seems to be working, they grow or get teeth or change their behavior in some way...... which, since I mentioned teething, it could be that too! I wouldn't assume that she is not gettting enough. If her weight is good and she is peeing /pooping like she should be, it may not be a problem at all!