Welcome @wmichelle, I hate going to the dentist anyway and to have a nasty burning taste and burning when swallowing after having some fillings has to be just awful. I did find some information on the topic here:

"Can dental fillings cause burning mouth syndrome?
This study confirms the opinion that burning mouth is multicausal. Hypersensitive reaction to mercury was more frequent than expected, but replacement of amalgam fillings relieved burning mouth in only two of five such patients, and one of these two patients had hypersensitive reactions to both mercury and gold."
-- Clinical study of patients with burning mouth - PubMed:
https://pubmed.ncbi.nlm.nih.gov/7817155/
Have you discussed the symptoms with an ENT doctor or your dentist to see if they might have some suggestions?