Not trying to talk down to you at all here, because I've had plenty of older friends and family members question all my "naive" financial plans for a couple years now, and I know how annoying that is. I apologize in advance if anything I say comes off that way, it's not my intention.
Just keep in mind that you are still young, and there is a massive amount of change and growth that goes on in your late teens/early 20s. Hell, I'm only 25, I'm practically a baby myself (as my friends in their 30s/40s constantly remind me), and my mind is nowhere remotely close to where it was 6 years ago. Completely different interests, goals, level of motivation/ambition, etc. - you get the point.
At 19, I had no problem living with my parents either. That's what normal 19 year-olds do, and the fact that you're investing your income puts you head and shoulders above the average - It also puts you in a great launching position for any future plans when motivation strikes.
My only advice is put yourself in situations where you're forced to grow. Don't let yourself stagnate. Keep an open mind when it comes to change, because it's going to happen and you'll be better for it.
It doesn't help that i don't have a career in mind
I still don't, and I've been working decent "professional" jobs for a couple years. Second piece of advice (sorry, lied about only having one) is surround yourself with smart, ambitious people now - One of the friends I met when I was 19 was calling me out of the blue at 23 to offer a job with a 60% salary increase. Cliche, yes, but it's true: most of the time it's who you know, not what you know.
Hope there was something useful in there. Best of luck to you, man.