Don’t sell yourself short: you are doing a much better job than you think.
You’ve come so far, you’ve overcome so many obstacles to get where you are, you can take on whatever work throws at you next. It wasn't always pretty, or professional, but you're learning, we're all learning. It might feel overwhelming, but you’ve handled much worse. All things considered, you have a pretty good track record.
Look around you: everything that you see, you made it happen up with just your brain. Everything you have you conjured up with just your brain. Your job, your house, the town around you, your friends, your children, your savings, all the things you own, all the people you know – it all came right out of your brain. You made that happen.
You started with nothing and you made all that happen. So when things appear difficult and overwhelming at work, remember: you were born with nothing, and you made a life.
You got this.