Ask: Red blotch on ballpython belly

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Hi guys,

I would like to ask about my ball python.
When it first came to me i noticed a little red spot on his belly

[IMG][/IMG]

Since it first came he is moody eater. And only want to eat 1small mice/ week. Now hes refusing his food.
His condition now the little spot on his belly just like this
[IMG][/IMG]

Do you know guys What it is.. I really need your advice
And every opinion will be appreciated.
Thanks