Greetings. I would suggest that you should consult the dentist who is treating you, since he/she knows the exact condition of your teeth and gums.

Hi dear. First of all do you know what your dentist did on your tooth. Its Root canal treatment. You might be having severe periapical abscess inside that tooth since there have been huge pus formation beneath the root of tooth & around its bone. Get complete treatment for that & don't pinch your gums coz it can lead to spread of infection in other areas. Sometimes buccal space infections results due to such actions. Let your dentist perform Root canal & mind it he/she must be a ROOT CANAL SPECIALIST becoz he/ she is the better judge of severity of your infection.