I have some art advice, but I'm unsure how useful it'll be here. So, first off, I don't think anything's wrong with your art. But if you think so, perhaps you shouldn't overthink when doing art. Maybe you think your art skills are lacking but that shouldn't stop you from making art. If you really think your art needs improvement then you could perhaps try something different, whether it be something as simple as rendering, doing a study, or even just doodling. Basically, aim to try something new, but by no means does it have to be a masterpiece.
Aiming too high and overthinking about your skills will certainly discourage you.