Does anyone else feel really good about solving a problem, only to have it swept away after you see other people solutions that are way better?
I always see there is a way better solution to mine and I feel bad because I didn’t think of it, or sometime not even understand it.
I feel like there is a playbook I haven’t read yet
Remember when you were, like, four years old and learning to print? It was big and ugly but you were eventually able to get the point across. As you kept writing, your letters became smaller and prettier.
Coding is just like that. When you start out it’s big and long and ugly, but code that works it good code. As you read and write more, you learn new methods and find out that some big ugly chunk of code you wrote could have been done with a native function instead and your code, like your handwriting, becomes more elegant.
Keep reading, keep writing. 
I think programming has made me feel more stupid than anything ever before. However, I think it’s one of the things that has made me feel smarter than everything ever before, too. It’s an interesting relationship.
Welp… I’ve been making a living close to 20 years doing this web stuff and I still feel inadequate. 
A junior developer will be given the smallest scope possible. Your first projects for a company or team will be so specific and you won’t be expected to implement a giant web tool. It’s reasonable that when you do large scope projects at first they won’t be the most elegant implementations. This opinion is coming from a friend of mine who is a full stack engineer, currently overseeing a full front end team including hiring. Just keep swimming and you’ll get there eventually.