Values are wrong. Look at my example, it was enough to darken some places to make the drawing read better. Try it yourself on your works. Just use a free graphics program (such as Krita).

It's very similar to shading light skin tone, only that the local value is darker, so the shading will be darker overall, and the highlights might pop more, due to the higher contrast. I think you'll benefit from practicing value control. There is a video on how to do a value study it in the shading course How to Organize Values. You can get it for free in the Proko Course Sampler. For me juggling five values right away was tricky. I first practiced two value studies, then when I felt comfortable with that I moved to three values, then four, then five. You might want to try the same. If you find it tricky to draw even tones at a desired value, you might want to practice doing a value scale. Cheers!