don't compare it to other people's stuff. it's all relative. i have problems with every piece of art i've done. i'd love to never pick up a pencil or brush again. but i do. it's not about the final product, it's about the being in the moment of creation. a teacher told me that the only perfect piece is the one in your mind, the one you're planning on doing.
i go into the comic book store and see tons of crap sitting right next to my favorite artists and wonder how these people got a job. i go into a "fine art" gallery and see the same crap that doesn't deserve a frame yet people buy it. i used to listen to the radio... no artist reaches a certain point when they are qualified to call themselves good or professional. some just want to sell stuff and make money. some dont, i know someone who has destroyed paintings after getting offered money. furthermore, there is always going to be someone "better" than you from a certain perspective. so just be yourself and the art will come naturally.
you say your vintersorg portrait is poorly done, yet you wouldn't part with it because it's close to your heart. EXACTLY! it's not about how it looks, it's about the thoughts going through your head when you did it. and the emotion you convey to others. your eye traces the aggressive scribble style linework as your memory or our thoughts trace the emotions. a perfect encoding/translation of that moment. but do we walk away with the same understanding? of course not. that's art!
so keep up the struggle! and thanks for sharing!