Tomorrow is another day. (You’ll improve today’s writing tomorrow.)
As Scarlett O’Hara said: “After all… tomorrow is another day.” Writing is always a process: tomorrow, you’ll be in a different frame of mind.
If today’s writing seems junk, a fairy godmother may sprinkle it with fairy dust overnight, and tomorrow you’ll think: “it’s not so bad… It might even be good.”
Acceptance is a wonderful habit for any writer. Accept what you write today. It's the best you can do... TODAY.