To help people better understand, here is an image of one of my bearded dragons, 2 and a half years old, extremely healthy and happy with her enclosure:
https://gyazo.com/5d9347c18990122557dc90af7514d635
And these are images of messages I had with my boyfriend the day I got the dragon:
https://gyazo.com/2e73908fb76b370b8aba41653a2a638b
After doing a bit of research I thought I knew why his head was shivering, but I was wrong:
https://gyazo.com/bbbef84e4243f1563918c509d7b20a81
The dragon was making gasping noises, and I couldn't tell what it was. It somewhat smelled as well:
https://gyazo.com/6577c2e5258b1f6571ad63d1a0751c40
Also, the dragon was covered in poop stains, and yet he didn't go to the bathroom in the box he arrived in. Rex is a dragon I am taking care of from a friend.
https://gyazo.com/46ea3506f59ad859d12f5a2d0ab37d2d