Ya, while you're in high school LIVE IN THE PRESENT, I know you need to plan for the future, but you still have a whole other year... From the time I was 8 years old all I ever wanted to do is be a pilot in the AF. I had talked to recruiters, took the tests, everything.... then my senior year I got my back messed up pretty good and the AF said "thanks, but no thanks". This was in '98. I don't know if they have eased their entry standards any or not, but that absolutely killed me for a long time. You don't know what tomorrow holds, so enjoy today.
Once you get into the "real world" you definitely need to have long term goals and a mindset. I still wonder what it could have been for me, but I'm thankful that now 15 years past high school I've got a great business, a great wife, two great boys.
Best of luck to you, I hope you have a great career, but like I said, enjoy the present. High school seems sooooo trivial now. I think there's maybe 3 people I graduated with that I still have "regular" interaction with. Some of my better (for lack of judgement) memories are from college. Truly good times... Then the bills start coming in! haha