It could be all of the above. I was diagnosed with "mild" sleep apnea and a CPAP hasn't really made an improvement on my day-to-day.
The main difference is that occasionally I used to wake up feeling completely hung over and near death, and now that no longer happens if I'm using my CPAP.
Most days, I am still tired - I am learning that is probably due to depression/anxiety (working on treatment now), ADHD (can't treat it until the former is stable), and poor stress management (undiagnosed autistic kid with zero social/emotional support).
The main difference is that occasionally I used to wake up feeling completely hung over and near death, and now that no longer happens if I'm using my CPAP.
Most days, I am still tired - I am learning that is probably due to depression/anxiety (working on treatment now), ADHD (can't treat it until the former is stable), and poor stress management (undiagnosed autistic kid with zero social/emotional support).