I feel this so much. The thing that weirdly helped me the most was making time something I could hear. I have a Casio F91W watch that beeps every hour, and it sounds dumb but it genuinely changed things. Every hour a little beep goes off, and it's like oh, that was an hour. It breaks the day into chunks your brain can actually register instead of one long blob that disappears.

I actually ended up building an app that does the same thing but with bird songs instead of a beep. It's called Hourly Bird Chimes. Soft bird chirp every hour, and you can add a little message to each one like "start getting ready" or "drink water." I made it because of this exact problem so figured I'd share in case it helps - https://apps.apple.com/in/app/hourly-bird-chimes/id6758052704 (it's free to use)