Your little dude is looking good. Have you tried nutribac dietary supplement for reptiles & amphibians. It's a probiotic and helps out with their gut flora prevent bad bacteria. You can lightly dust it to his crickets and has a lot of beneficial properties.
Glass cages for a chameleon can create many problems:
Ventilation issues
Lime scale on the glass
Reflections - that's why he keeps shaking cause he notices his reflection and thinks it's another cham
Damage to the tongue - he may try to get a cricket and miss. Cause damage to his tongue
Poor...
I noticed you have a glass enclosure. You may want to switch it to a screen enclosure for ventilation. It helps with their lungs and respiratory system. When a chameleon has his mouth open is because it's a natural tactic to help regulate body temperature. Poor dude is hot.