I don't think you can wrong on size. They made some that seem too little, some that seem too big and lots inbetween. I think smaller is better for a first project.
I like your ax, especially how you left the non-working end natural. A lot of modern guys would try to make that look neater by making it more symmetric, but the old timers that actually used them couldn't care less.
I do think you maybe over ground the bit. The angle is too acute and should be more arched, see: