I'm a brand new snake owner and I just got a female ball python. I think it's a female, she/he has yet to be prodded. She's full grown and got it from a kind of questionable owner. I've noticed something that I didn't when I first got her. Near/on her tail area, in the middle of her stomach, it turns slightly brown yellowish, there's a line and the scales don't look well. She acts and kind of eats alright. She ate at first, but after she stopped eating probably because I'm a new snake owner and still working stuff out, but it might not be. Is my snake sick?