Not that I can think of that you would notice right away, if heat and humidity were too low a respitory infection (to my knowledge) has more of a labored, wheezing or even whistling sound. Too high temps usually causes dehydration and madness, but I don't believe those come with sounds. As far as "crying" sounds, I don't believe I've ever heard one Out of a snake. I've heard a hiss, fart/burp, a puff/huff, and a whistle, heard of a wheeze but thankfully never had it. Could there be something he is rubbing up against like the glass Causing it?