Fellow solo dev here. I am happy for you that you saw this through.
I can not imagine spending so much time for so little return though. How many hours do you think you put into this altogether (not just including coding?)
It looks to me like if you were to do the math, you'd find that you were probably working for wages so low they'd be illegal.
It's really hard to estimate the amount of time. Even spending 40hr on it wouldn't be worth it from a purely financial perspective even if you ignore ads and other costs, and I spent many times that in terms of time.
But at the same time, doing this helped me reach over $6k MRR this year. Could I have gotten out of the tar pit faster? Definitely.