Hi, It looks like you are suffering from Aphthous Stomatitis which is causing you inflammation and sores in the mouth. It can be caused due to a number of reasons like Stress, Nutritional Deficiency [Iron, Vitamin B12 and Folic acid], hormonal changes, acid reflux, tongue trauma due to some sharp teeth or tongue biting habit, excessive intake of sour and citrus foods, uncontrolled diabetes and other immunocompromised conditions, etc. You need to consult an Oral Physician or a general dentist in this regard to get evaluated and treated. For aphthous ulcer you can do warm saline gargles with a solution of Benadryl and milk of magnesia can help. Apply numbing gel over the sore for relief from pain especially during eating. Take a multivitamin tablet for a period of 15 days. Avoid spicy, sour, and acidic foods. In case if still, the condition does not subside the physician can prescribe you to take a steroid course as it is the ultimate treatment in case if nothing else works. Hope I have answered your query. Let me know if I can assist you further.