red bump is due to periodontal abscess
this is developed as a result of accumulation of plaque
and food debris in the interdental area of these teeth.
there is bone loss resulting in periodontal pocket
visit a dentist
,get scaling and root planning done.
abscess has to be drained by curetting with gracey curettes.
use soft-interdental toothbrush to prevent plaque accumulation in this area.
clean your mouth after every meals.