There's some weird stuff going on with the depth of the helmet. Aside from some significant banding, it's inconsistent that each of the four orange quadrants would catch the light like that without casting a shadow on the next region.
Considering that this is the Castle Crashers knight, if you're trying to copy that style of helmet then there shouldn't actually be ANY difference of shading between the white and orange regions - it's smooth and somewhat cylindrical, so light should catch the same regardless of the patterning on the surface. In general I encourage you to think about where your light source is and how that would catch on each element of the character.
I really like the expression though, catches a lot of character without needing much detail.
Does that make sense? If I wasn't clear somehow (or if language is barrier; I notice you're Norwegian so some of the pixel art jargon may not translate, I don't know) just let me know and I'll try to explain it better :)
Yes, I know the helmet is odd, like really out of place. I noticed it while making it, but I just couldn't put my finger on it. So the part about it supposed to be cylindrical makes a lot of sence compared to what I was doing. I will work on that sometime in the near future.
Thanks for the feedback, I appreciate it a lot. Sorry for the late reply though, I had some issues the last few months.