Thanks for the help eishiya! I didn't notice at first that the colors blended as much because of the color options I had on my laptop display. I actually quite liked the bold look to the lines at first , but looking at it again changed my mind. 

The pinks all blend together a bit, but the black-ish colour stands out a lot, giving the whole thing a bit of an unfinished, flat appearance, even though you've clearly put the pixel work in. I think if you increase the contrast between the midtone and the shadow, and decrease the contrast between the shadow and the "black", it would give the Lickitung more volume.

I tried to make an edit to adjust the colours (middle). On the left is your original, and on the right is another edit to make the lines thinner. Having the lines double up in corners makes them look lumpy.