HELLO AND WELCOME TO HCM FORUM ,
according to the dental history provided by you it is clear that your lower left wisdom tooth has not erupted fully, it is impacted.
Therefore ,in such cases a gingival flap usually covers the tooth partially, which gets inflamed and infected with the food debris, causing pain.
Sometimes,
impacted wisdom tooth, due to its abnormal placement in the jaw can impinge or exert pressure on the sorrounding
nerve supply, causing
severe radiating pain.
I advise you to visit an oral surgeon soon, he/she will click x-ray of your tooth and accordingly plan a treatment.
kindly perform warm saline rinses(3-4 times/day), you can even use an antibacterial mouth wash ,twice/day, this will take care of infection and swelling if present.
i hope i answered your query,
i wish you good health.