Hi & welcome, jack may be yawning,all budgies yawn usually when tired and sometimes when the oxygen level in the room is to low.Scaly face is usually grey in colour,it usually starts on the beak spreading around the cere, eyes, feet & legs. It is very contagious, you will need cream from a vet or a very good pet store.can you post a picture ?
If it is mites, it would look something like this (my Skyla had an infestation and was treated accordingly with ivermectin; we had to treat all of our other budgies too even though they did not show any signs):
Fortunately, treating mites is not overly expensive. If you don't treat it, it can cause beak deformities and neccessitate beak trims for life.