K.T.
I used to have that problem with my kids... I just let repositioned them. I sometimes supplemented them with formula...Maybe she telling ya she's done with breastfeeding but before you would quit I would try to repostion them. here's a number you can call and ask them to give you breastfeeding tip when babies end up getting teeth and biting...###-###-#### its the local WIC office. if its not the prefix it might be 793 I get them confused sometimes.
I hope you have good luck...
Kel