Hello from JA
I am doctor Thomas, double board certified doctor, and I can certainly help you with this and any follow up questions.
Yawning can be from a number of causes, the most common being stress. Poor sleep at night can do it, and not snoring is not a sensitive indicator of what type of sleep problem you might have.
If there is indication, you need a sleep study.
Oddly enough, angina...heart disease can cause this symptoms.
Hidden lung problems.
So Even though it is benign in most cases, it should prompt a work up from your doctor, complete exam, EKG, routine labs, and consideration for a sleep study if indicated. OK. If you have further questions or details, use reply to expert. Otherwise please choose a positive rating . But, still come back if you need to…think of something later, etc. Bonuses are appreciated.