Right-click the actual image to get the image url..
You're adding way too much detail without cleaning up your lines, there are darker stray pixels, even clusters in strange places.
You should use a lot more contrast and some hue shifting.
Reduce the amount of details to get cleaner shading and make sure the basics like the smiley being round before you move to the next bit.
Eyebrows tend to be important for smileys, but you've added all kinds of wrinkles and details that fight for attention..