Probably a pulpitis (inflammation of the pulp) caused by removal of the decay and trauma to the pulp. This is a common occurrence after the removal of decay and placement of a filling. Most of the time it resolves (reversible pulpitis), but sometimes it is not if the decay is deep (irreversible pulpitis). In those cases the pulp (nerve and blood vessels) need to be removed and filled. This is called a root canal. Go see your dentist. You may also have gingivitis (inflammation of the gums). This is easilty resolved with proper removal of the plaque (bacteria) by flossing and brushing daily. If, however the gum inflammation is causing bone to resorb (periodontitis) you may need to have deep scaling and/or periodontal surgery. See your dentist.

Robert A. Stoner