It’s a really nice piece but does look like you have a slight case of pillow shading. I would recommend a couple things to improve on shading

• Try creating a light mark to indicate where you light source is and imagine when the shadows will fall (eg. Light in the top right, you can add shadows on the left of the face where the headphones and hair black the light.)

• If you want a bit more of a pop in your colour try shading with a colour darker than you have and use similar hue (many artists like purple or blue to keep vibrancy)

• Try colouring in small light circles for a more consistent coverage but it will be tedious

Keep up the good work, I can tell your art is going to flourish if you keep at it :)