Thanks for your query.
I advise you to apply cold compresses over affected area,dive her paracetamol
for pain and fever.
At the time of teething babies put every thing in their mouth which leads to diarrhea
.give oral rehydration solution after each loose stool
.give coconut water,curd,mashed banana.boiled potato.
i suggest you to observe her swelling and in case it increases and fever does not subside.take her to pediatrician
Your baby will be fine.