It's known as pericoronitis , which is a common condition in which the gums get inflamed and trapped between the upper and lower wisdom teeth, so wen ever food gets lodged between the teeth and gums , pain aggravates . I would suggest you to do salt water gargle 3-4 times a day ,that should relief your pain , and get that excess tissue excised under antibiotics cover , and even after doing all this you get back the pain and gum swelling, extraction of the tooth is advised

If your wisdom tooth is in awkward position the best treatment options is to get it extracted after initial pain relief For initial relief do betadine gargle with 1:1 concentration of betadine and water. U can also aplply antibiotic gel like metrogyl dg gel on that area 3-4 times a day to get quick relief. Finally go for extraction of that tooth