It didnt take "forever", its perfectly understandable, really.

You did a good job, and I can see you are good at doing shade and light on Wings,
If you want to get better, darken the areas you know will be in the shadow of something, such as underneath features or body-parts (such as underneath chins/mouth, below forelegs, etc)

Keep up the good work and dont let things get in the way of things you need to do yourself.

I'm actually going to try that thanks ;3