I can definitely help lessen the blow but whether you choose to internalize what I will say is entirely up to you and your respective levels of anxiety at any given moment. The honest truth is that you felt it before and you'll feel it again and even when you surpass the people you look up to you'll keep feelin it.

Visualizing something and having it come out all wrong is just part of the process and the process is never ending. i'm really good at visualizing things in 3D space but I'm terrible at internalizing anatomy. I need/use reference material a lot. You'll naturally have some strengths and some weaknesses and you just gotta not beat yourself up about it too much because every artist you know and follow has been there and almost certainly still is there on occasion

as a composer i wanna say... go with the flow!

i often get pretty fully formed ideas in my head for songs or segments of song (including arrangement, expressions, mix, overall vibe etc) and that stuff is almost impossible to keep in your head intact as you work to realize it. i used to get very gung ho about chasing the original vision, but these days i like to see what comes out and kinda go with that instead. ill continue to use my ears to see if anything delightful happens. it allows me to surprise myself in a positive way instead of getting frustrated because the synth patch doesn't sound right (prompting frustrated tweaking, during which my Song Idea starts to evaporate from my brain) or i can't get the chords right, or whatever.

i think this probably applies to any medium, though i will admit visual art is at a disadvantage bc music is inherently abstract, so you can't like, compose a tree and think "it doesn't look like a tree". but still thought i should mention this because it was a problem for me for many years, until i switched up my thinking about it. and i think it's improved my music too!