M.W.
I only breastfed one side at a time. So I let the child feed till they came off or fell off (because they fell asleep....) Rarely did I have to break the latch unless I needed to take them off before they were done. Although my babies were either fast eaters or my milk came out fast. They were both done within 10 to 15 minutes tops! And that was a full out feed where they were good for a couple hours.... My son did have a VERY strong latch as well so sometimes even after he fell asleep I would have to break it.
I would think it's coming from you probably producing less asa she is getting older or she is going through a growth spurt and is trying to make your body produce more. If you've nursed her this long and never had pain in your breasts, you have been doing it right!!!
I proudly nursed both of our kids anywhere and everywhere. My milk dried up when our daughter was about 6 months. (I was doing daycare and she had to usually wait for me to feed her.) Our son was nursed for 18 months ON demand as I was then staying home and farming with my husband.