gimps resizing is literally shit.
i did 256x512 at first, then i resized back to 512x512, and ofc the minor details got all pixelated, so im most likely going to just remove them.

Looks weird as hell. Looks like you've made this by triangles. These sharp angular lines looks too awkward. You'd better use pen tool for making objects roundish where it needs.
A nose is too long. Eyes seems too small and stretched.
Say truth, was you too lazy for drawing ears, right?