Thanks for posting the query,
Wisdom tooth are often tilted in position and impacted in the jaw bone which leads to pain .
This area is difficult to clean so it often invites bacterial infection leading to redness
, inflammation and swelling of the overlying gums known as pericoronitis
I would suggest you to visit Oral and Maxillofacial surgeon and get checkup done .
Take an OPG x-ray of the tooth.
Probably you have to go for extraction of the wisdom tooth.
Take a complete course of antibiotic and analgesic
Donot irritate the inflammed tissue .
Take saline water gargles 3-4 times a day to give a soothing effect.
Maintain a good oral hygiene , use chlorhexidine
mouthwash gargles twice daily.
Hope this helps out..