This is absolutely adorable! You did a wonderful job on this icon. It's the right size, the right colors, and has just beautiful shaping done to it all together. Not to mention, Cubchoo is one of my favorite Pokemon, so that gives you a bonus in my book! It also has excellent quality done to it.
This is a critique however and I have to give you pointers on how it could have been better. Let me see, you could have made it so that the icon was doing some more than just blinking, I know it's difficult to animate but you're getting there, maybe you could have tried making it move side to side or something, to be a bit more creative? That's the only thing I can really find to criticize on here.
Ok, list time! Don't pay too much attention to the stars. This will mainly be an improvement list!
• Symmetry is really important! It looks really good, only the mouth looks a little bit like it's leering off to the right.
• The animation is smooth, but I would probably make it blink a little more to make it look more natural. Usually the best pattern would be "Blink..Blink............Blink.........." if that makes ay sense. So like two fast blinks in a row, and then a longer pause, and then another blink, if that makes any sense. If not I could send you some examples or something. C:
•Shading is especially important if you want to give it another dimension. I can see you started around the ears a little bit, but don't be afraid to do more. You can also use different shades and just gradually get lighter and lighter until you reach the base color. This will make it look a lot more finished and will make it look more... real so to speak and make the face look even more rounded.
• On top of shading, don't forget lighting! If you want to give cerain things a little more shine to them, add a little white dot to the nose or something. This might apply more to other pieces with hair or something, but it's a good technique to know anyway. Just think about shading but instead of starting off dark, start off light and get darker until you reach your base color. Once again, if you don't get it I can send you some examples. C:
I hope that helps, I know I kind of suck at explaining things but uh yeah!