Thank you. I will keep these in mind.
Your journey is a source of motivation as well.
Now, technically the FDA doesn't force that, all they specify is that some standard procedure must be followed, and written evidence must be produced upon demand showing that the procedure is followed. So you could contrive an example where a cowboy coder made his own sqrt() and completely broke it, and that somehow led to the death or injury to a patient, or an elevator going into free-fall. or a fuze detonating. sure. Is that likely to happen? absolutely not.
Regardless of how thoroughly a system is planned in advance, programmers are not automatons who mindlessly fill in the last few blanks. They must make choices about the code they write, and that is absolutely a part of the overall design. If that code fails a code review, well, then it gets rewritten, but that's ancillary to my point: programming is design (albeit at a lower level than the overall system design).
Looking back what has helped me a lot is being surrounded by more experienced engineers that were good at teaching (those are quite rare I discovered later). Other than that, read a lot of code, write a lot of code, and keep reflecting on what areas to further develop. Be kind to yourself, this space is huge and no one’s is an expert in all of it. Burn out is real, especially when struggling alone for too long. One thing that has helped me as well is to realise everything in software engineering has been made by humans. None of it is actually ‘unknown magic’, just keep digging deeper to find out how the thing you’re struggling with works on a more fundamental level. The LLM age has made this so much easier.