You can't rely on the time you took to come up with a working solution, as a sign in evolving the potential to become a great developer.
But you know what you could take as a sign — how involved, and poised you got, for figuring out a solution that satisfies all the requirements; good for you for coming out with it; notwithstanding the time it took. That is a very good sign. :)
Happy hacking, and here's one to many more cool things that you shall come to make. 🍻