Pretty cool but you need to work on the proportions. When looking at a reference make sure you add no detail until the proportions and shapes are as closest to it as possible. I'd recommend looking at the drawing through a mirror (so it's flipped) or flipping it upside down so you're not as familiar with it and see your mistakes. If you do this before adding any detail you'll realize what you have to change before it's too late.

Good job, keep drawing!