Of course you can overfeed a chameleon - and lots of chameleon in captivity are definitely overfed.
In nature you will have days, weeks and even months without any food. As soon as an chameleon sees an insect, he will try to catch it. There is no safety he will find tomorrow same amount of food, so this chameleon will eat as much as he can. Chameleons aren't domesticated pets, so they will show same behaviour in captivity.
People don't remember this at home. We don't imitate longer periods without food or shaded days without a really sunny place to warm up and fasten metabolism, lots of people even don't provide a lower temperatured winter rest. Our chameleons can't climb and walk a hundred feet to look after females or feeders, they sit in a small cage. And remember, reptiles do not use 70% of their energy to keep their temperature, they just walk to a sunny place and that's it. They need a lot less food than we as mammals or our dogs and cats do. And they take more time to digest food even in a warm place (humans need some hours to digest food, some reptiles need three or four days). Of cause, feeding is fun for us to watch and an employment for our bored animals at home. But the result of feeding too much will be fat livers, renal diseases, gout and females laying 80 eggs and decrasing life time (although they could lay only 20 restrictively fed, too). All those things aren't that seldom at the vet's.
Your feeding amount is a lot, I wouldn't feed worms as regular food. A chameleon with six month should get its first days without food, becoming more days without feeders on and on. A restrictive fed chameleon will become older (and healthier) than a really much fed one.
