Poor thing..... he doesn't look well...
To me it seems like it as something to do with his eyes.
What is your lighting set up? What Uvb light are you using and I would suggest you dont use a basking light at that point. You should keep your temp at about 75-78 F. Your humidity shouldn't be too high in the cage, to prevent any infection. Although, you should put him in a plant, in the bath, and mist aroud it (just not on the chameleon, but on the leaves) for about 5 mins., so he can see that water is there for him to drink of the leaves.
Also at this age they can eat up to 20 small crickets a day. He should eat as much as he needs.
If your crickets die, maybe you are not giving them enough hydration. Try pieces of carrot and some cabbage or anything that could contain water.
I hope that was helpful to you and I will answer all questions that I can