Cute! I would say that you should work on keeping things simple right now. Do some real-life studies on anatomy. It's easier to draw stylistically when you understand how things look un-stylistically.
I'm also curious which drawing program you're using? That huge space surrounding your drawing, and the non-transparent background are telling me that you haven't figured out how to do those things. Out of personal experience, I recommend Medibang Paint Pro. It's really easy to figure out how to do things like that in that program. It's also got a stabilizer, which could help with your shaky lines.
Are you drawing with a mouse? That could be the reason your lines are so shaky. If you really care about drawing, then I might suggest investing in a tablet! It'll do wonders!