unusual insomnia problem

[Alaska]

I use a cpap at pressure 6 with varying degrees of success - mostly its pretty successful. For one of the first times in 4 years or so, i am experiencing long wait times to go to sleep and long wake times when i wake in the middle of the night. It took several hours on saturday night to fall asleep, maybe 3 (normal time is 5 minutes) and i woke up for a few hours later in the night. Sunday night, fell asleep in a little over an hour and woke up for about 3 hours 3 hours later. When im sleeping good, i wake up 1 or 2 times and fall right back asleep - for what its worth i use an audiobook to sleep and it usually has me back down in minutes. Unfortunately i have been getting a lot more of my book done lately because of not falling back to sleep.

I have not been drinking alcohol, i have a strong coffee at 8 am and thats it, nothing else caffeinated. I am a competitive athlete aged 49 and attributed the first lost nights sleep to thinking about the competition, but last nights sleep was after the pressure is off as i am done for the week. On the 2nd night i didn't have much in the way of extra thoughts or worries. It is quite similar to jetlag after flying to europe. The only abnormalities in my schedule/habits lately is 5 days ago i stayed up till midnight playing a video game, instead of my 10 oclock bedtime and i did take a small dose of liquid melatonin maybe 4 days ago. Could i have screwed up my circadian rhythm somehow? I exercise a lot (around noon) , take vitamins in the morning, and do spend a lot of time in front of a computer screen surfing or playing games (although i had minimal screen time on the days before sleep probs).

[SewTired]

Thyroid, blood sugar and blood pressure issues are the only things that really comes to mind when you don't have other health issues or meds. I think extended screen use can cause problems, but you say you only started using it, so likely not a problem. Also, changes in vision can cause low grade headaches that you don't even notice after awhile and they can wake you up and make it hard to fall asleep again.