Not wanting to cause psychological damage, however I do not think your effort would be helped if you only have the infamous MS Paint as tool. If you want to have potential of being featured in Pixel Day, then I would suggest you to install a proffessional art programme.
(Should not actually comment since I am much, much more worse in drawing and generally in anything creative)

Okay, honestly, the art is so-so!
however, if you really want to draw well, go look for tutorials and other theories of fine art!
and since this is pixel art, look for lessons on pixel art!
You can if you want to!
I hope everything works out for you!