She doesn't look fat from the pictures so she might just be going through a growth spurt? If she's only just over a year old then she'll still be growing so it could just be growth.
I think every snake gains weight differently as well, so it could just be your snake growing very quickly at this time.
I am not an expert but I think it could just be a growth spurt. Long as your snake is 'bread loaf' shaped, I don't think you need to worry
hope that helps a bit, however, we'll see what other people say as well
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