My friends and family have always said I have a knack for writing. I started writing novels at the age of 9 and produced a 300+-page work at age 12. I also wrote 2 others - a 486-page novel at age 13 and another one at age 14. I even planned a 12-book series at age 15 but didn't finish the first book. I wanted to be a published author way before my teens but unfortunately I procrastinated and the business of high school wiped that dream away. My first novel was about a prophecy among talking eagles and I utilized a lot of zoology - such as eagle behaviour, how they hunt, mating dances etc. They also had their own culture, their own language, and stories. The writing style was similar to, say, David Clement Davies and his books "The Sight" and "Fire Bringer". Since I know for sure that close people will be biased about my abilities, I'm just wondering whether I'd be considered a "genius" or just "a little better".

this is compliment trap if ive ever seen one.
It would be best for all if you ceased to exist.
I would also wager that the books were shit. Like, really shit.
try writing a GOOD one, though.
normal behavior->normal intellect
and
not normal behavior->genius intellect
And even if you wrote really great stories, maybe you're only really good at writing stories, which would necessarily make you a genius. Either way, determining whether or not you are a genius is pretty pointless in the grand scheme of things.
And whatever you decide in that regard, don't let high school dumb you down.
You should ignore all those people who put you down because you truly are talented, and you should never let anyone ever take that away from you :)
Lots of people can make up stories but not everyone does/wants to.
I made up short stories/poems from a very young age. Every time something happens that I want to remember I put it in a story or little poem.
I think it was because I was brought up on songs with stories behind them, all of which I still luv today. I used to be embarrassed but it took more effort NOT to do it!