Judging by your description, it is most likely a fistula which is a tract that forms from the
abscess of
your infected tooth that escapes out to the
gums. As long as the fistula in intact, your abscess can drain and slow down the spread of the abscess but if the fistula closes up, the abscess can spread rapidly through your face or neck area.
I would recommend seeing a dentist and getting treatment started.