It is not the breast feeding per se that causes areolar stretching - it is the pregnancy and the hormonally mediated breast enlargement that cause it. Once breast feeding stops and the breast achieves its new dimensions you will need to decide if you are happy with the shape, size and location of the breasts. If not - a Breast Lift (Mastopexy) can BOTH reduce and make the areola perfectly round while lifting the breasts and making them perkier.
well, i don't think so this matters when it comes to breastfeeding. size doesn't mean anything. if u r concerned, you may wish to contact yr gynae and hv a chk. if i remember correctly, both sides r nvr the same.
From what I know from my other mummy friends, your breasts and nipples will never be the same again. In fact here's a popular joke pic that is circulated amongst breastfeeding mums that expresses this fact