Firstly, don't be worried, it would not help you as Aphthous ulcers are related to stress also. These are common in the oral cavity and are associated with lack of trace elements and certain nutrients and many, many other causes.
Most often, these ulcers settle down with or without treatment in a few weeks and can be recurrent. See a good internal medicine physician who can assess you to rule out the major diseases related to lack of immunity.
Treatment is mostly symptomatic starting from creams that are safe to be applied in the mouth, they include a combination of oral barriers creams to cover the ulcer and reduce the pain and simple antibiotic creams. Many doctors prescribe vitamin tablets and iron supplements but there is no dramatic improvement.
So please focus on reducing your stress and anxiety levels.
See a good physician, most aphthous ulcers are troublesome but not dangerous and follow his advise.
Maintain good hydration.
Avoid oral trauma by changing sharp toothbrushes and strong toothpaste.
If possible avoid tongue cleaners or vigorous tongue cleaning.
You can take Reconia or any good brand of trace element and vitamin supplements.
Keep your lips moist with a good vaseline cream and if your are mouth breather, change this practice.