I think that's quite good playing.
You said you tried playing that once? Most likely, he didn't learn to play that piece that well overnight; he has probably spent countless hours practicing it.
But playing the piano is very important for me, and i will begin to practice much more than i have before, but do you think it's already too late...?
Late for what?
If you want to be a 14 year old child virtuoso and you're 15; I'd say it's too late.
If you want to learn the Beethoven by tomorrow, it's not too late although it is probably unlikely.
If you want to practice 10+ hours everyday from now on; I would say you can definitely accomplish this if you're dedicated enough.
Whatever it may or may not be too late for, you should at least try!
So lesson nr 1: Do not compare yourself to others.
Personally, I strongly disagree with this comment in this post's context.
Being able to compare yourself to and compete with others is a hugely beneficial tool. Here's one story why I think so:
Several years ago when I studied for my SATs, I took a small group class. I scored 1250ish on a diagnostic test, while one of my friends who also took the class scored about a 1500. Just being aware of this difference made me and my other friends study much harder. We were lucky that our teacher was able to manipulate the small group dynamic and make a game out of memorizing vocab, solving problems, and scoring higher.
Of the 7 people who took the class, 5 of us scored above 1500, 1 scored 1490, and 1 person scored in the 1200s (this was a random student who didn't really know any of us and merely showed up to class). I attribute the high scores to a group of friends trying to one up each other. If we weren't constantly comparing ourselves to and competing with each other, I think only 1 of us would have scored 1500+.
Also, note that I took group classes for SAT II Bio and SAT II Writing with my friends. Most of us scored 750+. I took private tutoring for SAT II Math IIC and only scored 690 (Math was my strongest subject by far).
This brings me to my next point about complacency. For me, the worst character trait is complacency. If you're constantly aware how other people play and strive to play as good or "better" than them, you'll never develop complacency. The only exception is when you actually play "better" than those people. I was thinking of writing another story but I don't want this to be a TLDR.
If you're curious why I use quotation marks around better, I'm only going to say subjectivity.
Anyway, since you realize he's much better than you at his age, the most important thing you have to realize is that there are things you can do to improve yourself to hopefully be better than him. My advice, however, is why compare yourself to him? There are many great pianists to compare to... Just keep in mind that getting to a high level of anything will probably take a lot of time and dedication.