I wouldn't worry about her intake unless this lasts longer than a week to ten days. If you think something else may be going on (a cold that didn't heal, an ear infection) then seeing her pediatrician is a good idea.
Try to encourage her to eat at least every 4 hrs. If she will nurse and take a mostly full feed, don't pump. If she refuses to nurse, then pump. Don't follow with a bottle or a cup, unless she has refused to eat for two feeds. By offering a substitute, you reinforce her refusal to nurse, and if I understand correctly, you want her to nurse longer, right?
Teething is a real pain, some babies don't do well at all. Some teeth are harder than others too. The bottom front are usually pretty easy though. :? At least in my two kids.