hello ,
thanks for writing to us,
After reading through your query it seems to be a cheek bite,
the white line running through the inside of the cheek is usually from accidental biting on the cheek while chewing, it is sore and painful.
You are not complaining of any
tooth ache so i assume it is not from an infected tooth .
For the gums i will advise you to follow a proper daily oral care regime.
brush your teeth with a soft bristle tooth brush twice/day,
use a mouth wash once/day,
floss your teeth once/day.
For the
blister on the inside of the cheek i will advise you to see a
dentist as it might require a thorough clinical check up followed by use of a topical ointment and try warm saline rinses(3-4 times/day).
i hope i answered your query,
i wish you good health,
thank you.