Oral Aphthous Ulcers are a manifestation of stress! Please increase your water intake. Sleep disturbances also interferes with your melatonin cycle and causes stress. If your job entails you to work in shifts then stick to one shift. frequent changes in shift timings also causes a lot of stress. You would be better off changing jobs if your employer insists on frequent changes to shift timings!

Hello. Based on the history you have given, I am assuming that you are having untimely eating habits and having a less nutritious food, which may have lead to gastritis or vitamin deficiency. So the main thing you should follow is a healthy diet.avoid taking spicy ,hot ,chilly food items , avoid smoking ,chewing beetle nuts , alcohol, take vitamin tablets ,apply local anesthetic gel to that area ,have tender coconut, buttermilk .have lot of fresh fruits and vegetables, take fresh raw sprouts twice daily, have a glass of milk and egg white. If you are not satisfied kindly consult a physician for further management.