Well,my dd is 13 months and still feeds more then that so I would say that seems normal to me, or at least no unheard of. If she is teething she probably wants the comfort and also may be having a growth spurt or something.
I think they are all different. I know some babies who almost stopped nursing around a year whereas I can hardly imagine dd ever stopping she is such a milk monster
Bfing will help ease the pain of teething. 2 to 3 times a night doesn't seem excessive to me. According to this information on sleep studies half of 12 month olds still wake, no matter how they are fed or parented. You might also like the isis website.