Have to agree to disagree again.
The ducking in the video is displaying a respiratory problem. If you view the video on a large screen you should be able to see that it's breathing is *not* normal. What I am seeing is what I call abdominal breathing or body breathing (whole body moves like it's struggling to move air in and out), it's also open mouth breathing, and I bet it you listen closely you can hear clicking.
It's eyes also look sleepy to me.
@Tsam88, can you hear any clicking, popping, or anything else?
I've had a few like this. Some recovered on their own, some I treated with antibiotics and they recovered, but some died even with treatment.