We already talked about perfectionism. But I think that this is good opportunity to look at things from a bit of different point of view. I am proud of myself for going outside of my comfort zone. Posting less than ideal photo of myself. Going to the nightclub. Trying new things...
I am proud once I finish a piece. But once I start a new one I want to make it better than a previous one.
I think that is a perfect way to approach things, be proud of previous work, but always try to up your game too.