Don't worry about it. If you can afford it, take some time to think about it and explore your options. The older I get, the less important I think having a career is. Of course, it depends on your goals - but it doesn't sound like you have any goals, which is perfectly fine! I never had any goals either, but here I am with a nice job, a house and two kids.
I never planned it would turn out like this - I just studied something I liked and took the jobs I could get. I was accidentally good at what I did, I suppose.
Consider yourself lucky - you're young, and just the fact that you're reflecting over all this makes you sound like an ok person. You have endless options and opportunities, and it's a lot easier to explore them while you're young.
"Maybe I'm not meant to be around for very long?"
No one is meant to be one thing or the other. You might fall over and die tomorrow, or you might live to become 120 years old. Who knows? No one, that's who. Treat life as an adventure, and just remember that life is what's happening right here and now.