Thanks for asking the query,
Swelling in the gums indicates inflammation of the gums known as gingivitis
it shows symptoms such as redness, swelling, pain, sensitivity.
It could be an periodontal abscess
arrising from the adjacent tooth to confirm this an clinical examination by the Dentist
is required followed by an IOPA x-ray. If it is infection arrising from tooth, it is treated by RCT.
Other than this it could be an gingival abscess
due to accumulation of bacterial plague
and calculus deep in the gum pockets.
I would suggest you to get complete mouth scaling and polishing, root planing and currettage.
Use antiseptic mouthwash gargles twice daily.
Hope this helps out.