Well done @Phoenix_Rising that is truly awesome work. It's almost perfect!
What an amazingly speedy progression. I am very proud for you, please be very very proud of yourself. I admit I had a wee tear in my eye at your success when I saw that image. I have all your swatch images on my desktop and compared them, awesome, just awesome work.
The Oopsey - yes, it appears you added an extra stitch on the side, which you have identified, but you then included it all the way to the end without missing or adding any other stitches. Fabulous!
I am so, so glad to have been useful in helping you get into this crochet adventure Phoenix_Rising. A skill like this will be of enormous value to you for so many reasons. Mastery - you're mastering new techniques!
Hooks - yes, it was indeed wise to see how the adventure went before jumping in and purchasing items you may never use again. I have a thing for stitch markers, the pretty colours, I need them all !!! LOL
The bodkin is a shortish, fatish needle with a big eye, for sewing yarny things up. You can see some on the right hand side of @CheerBear's tool kit beside that awesome dragon. They come in various shapes and sizes and made out of plastic or metal. 
Toys sounds like a wonderful idea. A dragon huh, I shall go looky at the possibles while I await CB's wisdoms on thoy patterns. Because CheerBear will know more about toy patterns than I do, so I'd like to hear from her if she's got time. Can you do some internet searching for something that appeals to you PR? Free crochet toy patterns abound.
I found quite a few, discarded all but this one for various reasons - see what you think about the appearance Ravelry Baby Dragon Pattern 
This one is made by working in the round, which is a new technique for you. Would you like to learn a new technique or would you prefer to make a larger something using the skills you've just mastered? Which would be more comfortable for you?
Knitting needles sizes and crochet hook sizes:
You are correct, they are not precisely the same, but for most purposes, they are close enough. Because I know my tension and how I like a piece to look and feel when it's done, I will often go a bit bigger with the hook size compared to the needle size, but with thinner yarn, it's good to stay close to what it says.
Australian labels do not tend to give the full extend of information that UK, US and EU labels do, unfortunately. Australia (Spotlight & LIncraft) are really behind the times with their minimal information.
Holding the yarn
I also have another couple of images further back in the thread with the way I currently hold the yarn, so do try both and see how it works for you. The direction the yarn winds around either the pointer, or the little finger is the same so it stays on better. Also, it's needs adjusting often, so don't be concerned about it if you keep needing to readjust your hold.
How I envy you your violin playing, and how glad I am that you have it. I began playing the viola years ago. The stress placed on a neck injury meant it was impossible for me hold the viola and I had to give it up. You are correct, and I like your analogy, good technique is iimportant right from the beginning. In the beginning, you will also be holding your hand quite stiffly, allow yourself to relax. Especially relax the shoulders so you are not raising them to raise your work to see it.
I'm also pleased that the thicker yarn helped you see and feel things better. YOu have achieved a great deal in a short time. Very proud of for you. (if I may be allowed to be proud of what is your work)
You are so most welcome for the help PR. so welcome.
Thank you for being an excellent student. You are a quick learner and attentive to detail, I like that in someone I'm helping learn a new craft.
So, it looks like it's circles next. Cool. You can make baskets and bags and all manner of useful things as well as toys, out of circles. 
have a very pleasant night dreaming of the toys that you will soon be making and cuddling up to.