My first bet is apnea. You don’t necessarily have to be a snorer. I am a “silent” apnic, although we are rare, we do exist.
When you get sleepy during the day, drink a big glass of water, preferably cold. Stick out your tongue in front of a mirror. If you have a line or crease down the center, you are dehydrated. Drink an 8oz glass of water every half hour until your tongue is flat and smooth. Most caffeinated drinks are also dehydrating, so if that’s the problem, the coffee will make you more sleepy, but unable to drift off.
Some of us have caffeine hang around in our bodies longer than others, so never ever consume caffeine after noon. And always follow every cup of tea or coffee with a glass of water.
Another great thing I’ve learned is a small serving of whole grains right before bed makes a huge difference. Whole grians contain the building blocks of seratonin. If you give your body a shipment of raw materials right before you sleep, it will be more able to manufacture what it needs. Whole grains also contain tryptophan, which helpful to a lot of people. There is also some in turkey and other sources, but protein blocks the absorption of it, so the lower protein int he grains lets more through.
Do not give in to sleep at the wrong times, there is no winning if you don’t force your body to alter. No more yoga naps! LOL!
Good luck, and if you don’t get some relief soon then push your doctor to order a sleep study. These often take a long time to schedule, so act quickly. There will be plenty of time to procrastinate while you wait for an appointment to come open.