Ask HN: Not resting fully because can't sleep long enough

Hey founders! I'm working on a startup as a solo founder and realized that I'm only sleeping 5-6 hours per day for last few months. Don't think it's sustainable and healthy. I'd like to sleep 7-8, but just wake up early. I can't get myself to sleep longer or more. It's probably because I have too much on my mind and feel I have a lot to do.

Have you guys experienced this? How did you address it?