Hi..
Welcome to HEALTHCARE MAGIC..
I have gone through your query and can understand your concern.
As per your complain and presentation of symptoms it seems that you are suffering from
BURNING MOUTH SYNDROME and as you have white marks over tongue there is a possibility that there is
fungal infection in mouth known as
Oral Thrush as it is one of a very common cause of burning mouth..
Another common is
Nutritional Deficiency of Iron, Vitamin B12 and folic acid but if there is no improvement after taking
Multivitamin then Thrush can be a cause..
Nothing to worry as it does not seems to be like Cancerous..
You should consult an Oral Physician and get evaluated and treatment will be planned according to diagnosis..
As of now you can take supportive treatment like gargle numbing mouthwash containing Lignocaine..
Continue taking Multivitamin for one month..
Sucking ice pops and gargle with cold water can have..
Avoid hot and spicy food and take a soft bland diet..
Drink plenty of water..
Hope this information helps.