I think I struggled at least a couple months before I even got the hang of Rust. Read "the book" several times, didn't help. Watched several videos, didn't help. What eventually clicked for me personally was learn rust with entirely too many linked lists, I think I have read that 20+ times (still visit it sometimes).
6 months into it, I started getting better at organizing code and thinking more in terms of a data-driven approach (structs and impls) vs abstraction based (class and methods).
Bottom line is, everyone has a different approach to learning with wildly different times it takes to absorb knowledge. As for whether it's worth, well, it's still a relatively young language (compared to C, python, erlang, java) so you're already early. Another decade and perhaps Rust becomes as universal as C is.