From your post it is a bit unclear what you mean by feeling under-experienced compared to your peers. Is it at technical level? Work ethic/principles? Understanding of the whole technology stack? Or perhaps process in your company?
While any of these topics can be tackled and improved independently, little would contribute so much as literature on:
- Clean methodology from Robert C. Martin. In particular, "Clean Coder" (ISBN-13 : 978-0137081073).
- Software craftsmanship. In particular "The software craftsman" (ISBN-13 : 978-0134052502).
These should give you, in my humble opinion, some fresh motivation and abstract overview on software development in general.
I wish you the best of luck in your endeavors!