Aw, that is very, very cute! Seeing as this is your first time using a tablet, I'm very surprised by how clean it is! Certainly much better than my first attempt at digital art, haha. You are right, there are a lot of big differences between traditional art and digital art, but if this is your first entry into the latter, it is clear that you are going to do very well.
What kind of illustration software are you using to draw with? There are settings that will allow you to draw smoother, more fluid lines while you learn how to steady the stylus. Also don't forget to work in layers! It's very important to create multiple layers when you're drawing / coloring in digital art so it's easy to grasp what you're working with. Next time, apply the color on a separate layer - I promise it will help. :)
Best of luck to you!