My mother age 48 Non smoker Don't take Tobacco Recruiting mouth and tongue ulcer Past few months vitamin b12 normal 636 Vitamin d deficiency Have stain in theeth Inner cheek some area little bit swollen some time Also feel tingling  sensation in right parotid gland area Why feel like this ? When she take orange juice her ulcer not reccur reduce Brown/black spot have in inner cheek What is this ?? Or something serious like oral cancer ? Is it normal or something else Picture attached below