The answer is yes and no.
No, you will always want to improve, to do something more. I can't think of a single pro who says "Yea, I've peaked, there's nowhere left to go".
Yes, you should learn to appreciate your own art, your progress and to be proud of what you do regardless of your level. If you put the effort and are working to continuously improve and express yourself, and more importantly, are having fun, you're doing it right.
Both are important in healthy dosis and very destructive when taken in negative ways. You will probably also swing back and forth depending on your mood and feeback received.
