Should I stick with a track or apply what I'm learning in a library course

I'd say go for it. You can always switch back! And there's nothing worse in programming than getting discouraged. It's the most sure-fire way to walk away from it. One thing about learning multiple languages and multiple ways of implementing solutions is that over time you'll see patterns emerging. While different languages may write things differently, a lot of the coding that's done follows the same logic.

For instance, I just finished a Node.js module here and then followed up with an Express.js. When I'd gotten done with the Node.js things were quite fuzzy. But when I did the Express.js some things that had been previously covered in Node.js suddenly clicked for me. It's those light bulb moments that you're after.

Hope this helps! And whatever you do, don't give up. That's never the answer