Kittens and cats are great help with such things. Cute duck.
"Not great" is merely an opinion, interpretation, matter of perspective. "It's really good" is all of those as well. Fact: It's better than any duck I've ever drawn and I'm impressed at your kitten's amazing skills!
The more I look at it, the more I like it. It just didn't turn out like I wanted it to. Just goes to show it's best to appreciate what we have for what it is instead of comparing it to what we wish we had, which will always leave us disapointed.