I think you could use adding a few more colors to this. Also, try using MS paint if you're using GM's editor. GM is for games and the editor is the WORST pixel art creation device I've seen. My calculator has a better pixel art app than that. (seriously.)
The mouth, especially lower jaw, has some anatomy issues. I'm sure you can find a picture on google of a dog or wolf that shows the structure of the lower jaw. The ears are also a bit wonky; the left (its right) ear is okay, I suppose, but the other one is coming out of the top of its head.
Good luck continuing this piece!