The biggest lesson I took away from this experience in my own life was learning to leave tasks in a resumable state. If I did get to work on something, I would do my utmost to leave it in a state where I could come back to it and dig in right away. For code at work, I might break the code where I wanted to jump back in (uncommitted change) so a build would show me what line of code I was editing when someone threw up or doorbell rang causing the baby to wake, the dog up freak out, and my train of thought to be derailed for the next hour. That, and learning how to survive on what is essentially polyphasic sleep.
I found myself in a similar situation to yours... and then had a second child. If I had the time to track it, I'm sure the results would not be much better. After that much needed wake up call, what did you end up doing?
Lower your standards for everything. Work, cleanliness, relationships, hobbies.
Try to get to a point where you do housework while the kiddo is awake and entertaining themselves.
Some medium term planning helps. Cooking enough for 2-3 meals at a time so you don’t do it everyday. I used a meal plan that told me the groceries to get. Think of some other “life hacks” or corners you can cut for things you do a lot. Take some time for self care.
Worked out that If there were no delays; I would have 5 minutes at 7:25 to myself.
It was a much needed wake up call.