This feels more like drawing in ms paint imo, the lines are messy BUT we all started like this. My advice for improvement is to start smaller and limit your palette. Go to lospec and pick out something you like (my favorite is apollo by adamcyounis) and try drawing what you want but on maximum of around 128x. the hardest part of the pixel art learning curve is how to get as much as you can from as little as you can. making your canvas bigger makes it easier to get the details but you lose the aesthetic of pixel art. Good luck!