How old were you when you realized you are asexual and how old are you now?

I'm genuinely curious of when you're old enough to "know". I'm 18 and think I'm asexual, but could it just be my age (and maybe I'm just a late bloomer and I'll feel differently at 25?) I don't FEEL like I'll change because I feel like if I weren’t asexual I would be interested in sexual relationships like a lot of people my age but I'm not and never have been so far. It's confusing and I don't want to fall into the trap of forcing myself to eventually try something because that's the "normal" thing to do and then regret it.

https://redd.it/1x5q2m7
@asexualityonreddit