Ramsayi, I always hate when people say this but...
it's probably time to see a good reptile vet.
We all mean well and most people can help you by pointing out things you should change regarding diet or equipment, but you already must know that chams are experts at hiding problems, so delaying veterinary help can often result in the loss of your cham.
It might be gular edema, which can be be caused by oversupplementing and by undersupplementing, especially vitamin D3 or A.
You only mentioned dusting with calcium. There are many calcium supplements on the market. Some of them are unsuitable, as they contain phosphorus, which should definitely not be used--others contain D3 which is needed, but shouldn't be used every day.
Pictures are helpful, too.
Rather than everyone asking you a bunch of questions, one by one, the best thing is if you answer the "How to ask for help" questions:
Cage Info:
Cage Type - Describe your cage (Glass, Screen, Combo?) What are the dimensions?
Lighting - What brand, model, and types of lighting are you using? What is your daily lighting schedule?
Temperature - What temp range have you created (cage floor to basking spot)? Lowest overnight temp? How do you measure these temps?
Humidity - What are your humidity levels? How are you creating and maintaining these levels? What do you use to measure humidity?
Plants - Are you using live plants? If so, what kind?
Placement - Where is your cage located? Is it near any fans, air vents, or high traffic areas? At what height is the top of the cage relative to your room floor?
Location - Where are you geographically located?
Chameleon Info:
Your Chameleon - The species, sex, and age of your chameleon. How long has it been in your care?
Handling - How often do you handle your chameleon?
Feeding - What are you feeding your cham? What amount? What is the schedule? How are you gut-loading your feeders?
Supplements - What brand and type of calcium and vitamin products are you dusting your feeders with and what is the schedule?
Watering - What kind of watering technique do you use? How often and how long to you mist? Do you see your chameleon drinking?
Fecal Description - Briefly note colors and consistency from recent droppings. Has this chameleon ever been tested for parasites?
History - Any previous information about your cham that might be useful to others when trying to help you.
Current Problem - The current problem that you are concerned about.
