I also like your note about accomplishments. This is really important to feel proud about things you've accomplished. Finding joy in these small completed projects may motivate you in going forward. There's no point in feeling worse.
Everyone started somewhere and it is very likely that most of the brilliant programmers also made simple things in the beginning (and most probably were very proud of them :)), but yes - fighting your doubts is very difficult.
I feel like we should try to find someone who will give us a positive feedback to soften the frustrations. This may not even be a specialist in the field - show what you've done to a friend or family - added bonus: they will be likely even more impressed. We tend to be overly critical about ourselves, so it is useful to search for feedback from others.
Thanks a lot for sharing your thoughts!