Hi..
Welcome to HEALTHCARE MAGIC..
I have gone through your query and can understand your concerns..
As per your complain the symptoms looks like Apthous 
Stomatitis causing Apthous Ulcers and it can commonly occur due to 
nutritional deficiency of iron and 
vitamin B12 while other commonly occurring causes can stress, physical trauma caused by any sharp tooth,diabetes, 
allergic reaction to any medicine or food etc.
Nothing to worry, you can take a 
multivitamin tablet daily for 15 days, do soda bicarb gargles,if there is pain you can apply a numbing gel containing Lignocaine or choline salicylate and suck on ice pops..
Avoid spicy , sour and acidic foods..
The ulcers will get resolved in a week or even less..
Hope this information helps..
Thanks and regards..
Dr.Honey Nandwani Arora