If you feel groggy in the morning or just not well–rested even after 7-8 hours sleep, get your sinuses & lungs checked. Could be sleep apnea, but in my case I felt congested all the time. What I thought was allergies was actually the linings of my sinuses inflamed to the point of closing off air passages. Unclear if the root cause in my case was acid-reflux into the sinus cavities or exposure to dust from ground zero…
Fast forward 6 months or so... I have serious difficulty sleeping more than 8 hours, can hardly sleep past when the sun comes up. Don't need an alarm to wake up, and feel well rested after 7 hours of sleep. I'm also so much more productive at work, actually feel awake and can focus on things. Prior to the CPAP machine I don't think I ever actually understood what it was like to not feel tired, it was just my normal state so I was actually tired without even realizing it. It was a life altering change that didn't happen overnight. I've tried a couple times to sleep without the CPAP machine, and it just doesn't happen. I imagine its the same as sleeping before, I just notice how I'm unable to sleep now.
This might not be true for everyone, but if you're told you snore really bad, and don't feel exhausted all the time, but can sleep constantly... you may have sleep apnea and are just dealing with the symptoms without even realizing. It was absolutely worth getting checked out for me.