Not sure if it relates to you, but I discovered I have a "deviated septum", basically one nostril has collapsed. I have been saying for years that I am not getting "enough air".
They discovered this when I had my sleep apnea test. Also, I do stop breathing. I did breathe thru my mouth and wake with dry cotton mouth.
I always had the symptoms you mention with the short term memory loss, morning headaches, lack of energy, and total exhaustion.
I have found out that I have Chronic Fatigue Syndrome, fibromyalgia, disc problems in my back, and some problem with my left temporal lobe that causes these "seizures" which make me "lose time" and causes the memory loss and feelings of loss of control of my life.
LOVE my CPap machine and getting more air during the night; sometimes, I even wear it during the day as I sit in my bed and read or watch tv.
Seldom get those headaches anymore, but my doc put me on potassium .......he did a blood test and found out I was deficient and that caused the headaches. Who would have thought of that?
I use B12 sublingual tablets and also now take amino acid liquid every day. Because of my heart problems, I cannot use caffeine anymore. For the aching joints, I use glucosamine chondroitin which I have found is better than a pain pill. Once in awhile, I do take a muscle relaxer before sleep when my body seems all "tightened" up.
I go to pogo and do all kinds of puzzle and other gains to work on my memory. It seems to help some. I write everything down and try not to have to depend on my memory, which fails me.
I have a caregiver who keeps me on track for meds, appt's, but I still struggle with paying bills on time. I do that online and have receipts sent to my email so I know when I am due or when payments are made.
Sometimes, we just have to readjust to things changing. I am in my late 60's, but act like 80's. lol. It is a struggle just to get to the bathroom, and don't get out much either.
I am no longer allowed to cook without supervision or go anywhere by myself as I have gotten lost.
I just remind myself that the Lord knows where I am and what is going on...He does not leave me alone and is in charge. I am thankful for His love and faithfulness, his Mercy is new every morning.