Every one of my snakes lets me know in a diffrent way when they need to be left alone. My first ball python would give a huff, it wasn't quite a hiss, and push me away with his body. My blind snake snowy does that when touched no matter if he's in a bad mood or not, just cause he's blind and hates for me to touch him without letting him smell me first. What they mean by that is, say you loosesly dangled a pen next to your snakes body, when it touches them they contract and push out real hard with their muscle, it would bump the pen making it sway away and then bump back into them. You'll notice when your snake actually does it. Anyways, watch your snake very closely and take note of everything the first time you realize it's unhappy, cause they all show it differently and before you know its personality it is a sorta a trial and error thing. My baby brb is real hard to read because they are so unpredictable and they can strike at the weirdest times from the weirdest angles, for no reason I've heard. But I have even noticed that he does one of two things: he either abruptly stops moving and tenses up with his head turned away from my hand but his eyes turned to the back staring right at it,(that's how he caught me off gaurd the first time he bit me)or he will raise his head up and go into a mini-king cobra postion with his tongue flicking real fast. he only bit me that once cause i was putting in his water, I'd just got him home, and I think I bumped and scared him.

. He's only gotten me that once.