Brief Answer:
You may be suffering from stomatitis

Detailed Answer:
Hi, XXXX
Thanks for asking HCM.
I am Dr Rakesh Sharma answering your query.
From your description you seem to be suffering from stomatitis.
It is usually accompanied with bad stomach,and may be an anaerobic infection.
I would suggest you to go for a stool test for worms, ova, cysts, or amoeba.
They cause disturbed bacterial flora in intestine and in turn all the problems you are having.
The rash which spreads in your leg, you have not given much description about may be any thing. It is difficult to comment on it without description or a photograph. You can put some soothing lotion on it.
I advice you to take Fiber rich small frequent diet,fruits and vegetables.
Do drink lots of water.
You should take lots of curd,and may be lactobacillus supplement in capsule form.
Mean while you can have proton pump inhibitors in combination with pro kinetics empty stomach.
For constipation you can have mild laxatives.
Local antiseptic gel in combination with anti fungal and ant amoebic might do good to you.
Do ask if you have any doubts.
Good day.

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Brief Answer:
This can be fungal infection

Detailed Answer:
Hello again,
On a broader sense they are the same infection and their treatment goes in the same line.Candida is a type of yeast.Lets not go in to details of theoretical part.
Your lesion seems to have inflammation also, so your local application needs to be in combination with steroid for some period of time. later on you can switch to a broad spectrum antifungal application.
Get your self investigated for COMPROMISED IMMUNE SYSTEM which usually may be the cause of prolonged wide spread fungal infections.
Please consult your doctor to get yourself thoroughly investigate for all possibilities, not only local but systemic as well.
At the same time you can start other things as suggested in first answer.
Have a good day.

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