Along with other excellent advice given in the comments I'd like to tell that you need patience. A hell lot of patience because hardware is a completely different beast as compared to software. For instance, int i=0; i = i+1; will always work.

There will be a dozen reasons why your LED isn't lighting up, because the wire looks fine but it's broken internally. Or the Breadboard has a short. Or you just accidentally routed the power pin to the ground plane. Or someone just used a flash which caused the RPi to reset. Or sometimes, fuck you that's why. The amount of frustration that goes into this is exceedingly large because once systems get complex, it really gets difficult to track things unless you're extremely methodical.

This is not to intimidate you, but just to tell you that once you've finished pulling your hair out, (hint: why are engineers bald?) when the entire system works perfectly you WILL feel on top of the world. That is a feeling that no one can describe really but everyone of us has experienced it.

If you're planning to get serious, you will need mathematics. I never really cared for Math when I was studying for Engineering because it seemed pointless and I'd think, "There's no practical reason why I need this". BUT you absolutely need it, trust me. You'll be thinking like, "Oh yeah, I can do my stuff even without learning all this complex math (EE pun intended)" but when things fail, instead of poking in the dark, math along with basic principles allows you to understand why it failed, and what you can do to not make it fail, or even better, how much you can push your luck to make it barely fail. Each time you do that, your understanding becomes better. Hell, just grab some poor bloke and start explaining things to him/her, regardless of their wishes, and you'll realize that your understanding becomes super strong.

Tl; dr - Math and first principles, you need it more than you realize.