Cameron
First thing I would like to say is that you are doing a good job feeding that little dude. He looks good. You have got some belly on him, and that is a sign of good things to come!
I realize that you may have tied him like that just to take pictures, but if you always tie him like that I would advise you to not. If you are having attitude issues with him, tie him very close. Only give him about 4" of slack when you have him tied standing so that he cant move around much. That will help you a lot with him not wanting to stand still.
The other thing I want to point out is that it is early. Before you start him on any medication, just give him time. Keep working with him. Keep leading him around. Get the show stick on him. Mess with him. Find his "sweet spot" with that show stick. Find that spot where he just loves to be scratched, and when you scratch him there he will stop dead in his tracks. I would really urge you to not start him on any kind of Melatonin supplement early in the winter. You will have hair problems like you have never seen if you do.