I just stuck my hand in my ball pythons tank to pick her up and she made this whistling noise everytime that I touched her. I've never heard a snake hiss, but it didn't sound like what I would have thought was a hiss. It sounded like a faint whistling and I can't help but worry. Was she hissing at me and if she wasn't, is whistling normal? I should also add that she's the sweetest thing in the world and has never done anything out of fear other than ball up. Thanks for your help!