I've had chameleons with eye infections. Make sure that he is eating and getting water. Id keep a close eye on him and write down how long his eye stays shut, opens, looks inflamed, gets upset if you touch it lightly just in case you go to the vet you can cover everything. They use their eyes to eat and you don't want to let a infection go without ointment or drops from a vet, they can go blind or be in pain, so if it looks like he's in need of a vet, I would take him to be safe. Hope this helps you.