I am proud of you for working out this problem as much as you have, and putting as much care as you have into it.
I think you are overthinking the outside factors. Trust yourself that you wrote code to account for most outside factors. I feel like you are really on the edge of figuring out what it is. And you'll know which direction to take when you just relax into it and know that it's good enough. I think it is likely that the code is better than you think. You got it right this time. Trust that.
Yes, I am leaning it has to do with overthinking as well. I decided no to think at all.
No thinking! You are super intuitive. Trust your gut!