I Found Him W/ His Mouth Wide Open. His Kneck Is Swollen underneath. He let his toungue hang out quite a big but sucked it back up. Does anyone know about the swollen kneck b/c that seems very seriouse.
How about a picture? A swollen neck can mean that you have over supplemented him. It can mean something else, too. Regardless, you need to get him to the vet. It sounds very serious, and beyond a forum's ability to assist.
A photo would be very useful here. Another thought I have is are you sure he wasn't stretching prior to shedding? Chameleons will gap open their mouths and swell themselves up prior to shedding to help losen their skin and will wiggle back and forth at times. Does your chameleon show signs of shedding at all?
If not, swelling under the neck can be from several things, some of which can be very serious. A tongue hanging out is not a good sign if he was hanging it out for a period of time while opening his mouth - these symptoms are very serious. A trip to your vet is highly recommended.