It seems like an infection in the gum and the surrounding tooth area, apical gingivitis
It may require a surgical drainage
under antibiotic cover, followed by root canal treatment
and crown to be fixed in the tooth.
Please get it evaluated by a dentist
as early as possible, because it might turn into an Abscess and cause more pain.
Meanwhile, take over the counter analgesics like Tylenol.
Get well soon.