I am happy to answer your follow up question.
The virus that causes cold sores is known as the herpes simplex virus (HSV).Once you've had an episode of herpes infection, the virus lies dormant in the nerve cells in your skin and may emerge again as an active infection at or near the original site.
The most common cause of frequent canker sores are:Food sensitivities,Food allergies, emotional stress, hormonal changes, food allergies,a diet lacking in vitamin B-12, zinc, folate (folic acid) or iron.Canker sores are also called aphthous ulcers. Use a cotton swab to apply the mixture of half hydrogen peroxide
and half water for mouth canker sores.
The fatigue in legs you are having are not related to this & might be due to other causes.Its not to get evaluated & tested separately.
Physical clinical examination & tests are very much required to know the exact underlying cause.So I advice you to make an appointment with your doctor for these tests & examination to know the exact cause & then treatment will be done accordingly.
Hope this helped & I had provided you an excellent service.
My main motive is your satisfaction.If you still have any questions in mind,please feel free to ask.