So when I was cleaning his cage, Rango climbed out onto my hand so I just let him relax on my shoulder for a little bit and I heard a weird popping sound like a little hiss and then I heard a big pop/hiss when he opened his mouth. I freaked out because It was so loud, I've heard him hiss before when he is angry but his mouth wasn't opened all the way like when chameleons usually hiss. Never the less I made a vet appointment tomorrow. Which also worried me is that his humidity isn't too high yesterday it was in the 50s and today it's in the mid to low 60s.