If your story won an award, that speaks for itself. How many people can say their writing won any award? I know I can't 😅
I mean, I got some top writer tags on Medium now and then, but that's really just me riding my fluffy little unicorn into the sunset. And those are gone now anyways. I haven't published anything worthy in a while.
And I think age has nothing to do with how skilled you are, or how skilled you are allowed to be.
A lot of people actually aim to write stories in YA categories, since those often pay the most if they ever make it into the market. That supposedly happened since J.K. Rowling kicked it off with Harry Potter. (I know a lot of people trash talking her writing, but honestly? I think the millions in her bank account are more than enough to brush it off as jealousy)
So I wouldn't look at you or your age to make a hasty judgement call. I mean there are 8 year old kids who look like competitive bodybuilders. Sure we could argue about whether or not their parents are doing something really bad in encouraging or maybe even forcing it. But when it comes down to it, I wouldn't hesitate to ask that 8 year old how I could get to look like that. Him being only 8 year old doesn't hold much weight compared to him looking like he knows his stuff.
If you are a good writer, your advice is invaluable. If someone still decides to doubt you because of that, that's their loss. In your case, it sounds more like you're suffering from impostor syndrome. Again, I liked the story that I found. It was well written and though I expected the plot twist a little before getting to the last line, it still felt like a great ending.
And regarding my research, I didn't even think that "Into the daylight" was only shortlisted, but not awarded (I jumped into reading it right away and didn't spend much time looking if there was more info on any award or anything. Being mentioned online by a third party is enough glory in my book already)
Anyways, good luck on the path and keep writing. Just remember: There's nothing bad about becoming a published author in the YA genre. 😁