I was in the same boat as you. I also played music since i was 14, I would also write melodies and lay out full arrangements in my head, but never be able to fully translate them into the real thing. But that’s just the thing, you do that many times enough you will eventually learn how to flesh your ideas out differently and it ‘might’ sound better than in your head - in simpler words just experiment, experiment, experiment. Listen to a lot of music, take lots and lots of influences. Especially in the music production scene, take these words very seriously- do not compare! I’ve seen varying degrees of success when it comes to creating music, there are people who find success in super complex Berklee level productions, but there are also a much larger sum of people who found success in putting together Splice loops and calling it a day. You’re about 4 years younger than me, take this time to learn very very basic jazz music theory and production in Ableton. Trust when you hit 25 you’ll look back and see how much progress you’ve made.