i think you should be but i also know that im never proud of my work
just keep doing it, eventually you will be, with also feelings of unproud mixed in. this is to drive you to do better. but, it might help if you can find some stories about other artists, artists whom you think are great, and discover all the times they've felt frustrated with their own work. there is no limit to what we can imagine, but there always seem to be limits on what we can physically do. so that can be enormously frustrating. but what makes it work is the imagination of the viewer, which you can play to. this can be easy to forget, because the viewer will never notice it when it works, they'll just think the artist actually did everything. but they didn't, and they were probably very concerned about this at the time