Weird neck/throat movements. Is there a term for this?

[Rebdr]

Ive been recording myself at night to get a better idea of whats going on. Ive noticed neck movements before I stir. This is the one with the best view.

Is there a term for this? Is it muscular? Or external jugular vein/carotid? Sort of looks like it balloons up and no matter how hard I try I cant recreate the movement  

I have constant throat tension during the day.

Ah it won't let me upload the vid so attached a still. It almost looks like a long balloon being filled up

[Rebdr]

After looking some stuff up, seems it is a sternocleidomastoid contraction which aids breathing.

Could a sternocleidomastoid dysfunction cause uars/apnea?