Here is a video of my 1.5 year old bearded dragon, Fancy. I noticed her breathing like this today while resting in her cave and it seemed abnormally heavy. She is not making any noise, but it seems like her body is rising up more than usual. I don't know if I am being paranoid, so I wanted some more experienced people to weigh in! Thank you!
https://youtu.be/5EN48UOzE_c
https://youtu.be/5EN48UOzE_c