All good advice here.
I was the same as you in the mid 80's. In my room studying for initial Private Pilot Licence subjects in late high school. My parents thought I was doing school work. Subsequently, my marks in yr 10 were well above average but yr 12 finals were pretty average at best.
This is something I regret to this day. Life worked out OK though, now a Captain with . . . . .?
Of course, smoking hot chicks, cars and heavy metal got in the way of school too.
Relax, concentrate on school and the things above.
Besides, it would appear that aviation industry expansion may be pretty stagnant for many years so time is on YOUR side. No expansion at the top end means not much employment opportunities all the way down the rungs of the ladder.
Boom/Bust, Short Feast/Long Famine.
Once every decade there is a reasonable amount of Pilot jobs out there for 2 or 3 years, then terrible for 5 - 10. In my opinion, 2013 was the last of these couple of good years (although this last Feast lasted fairly long). I believe we are now at the start of the next Pilot Employment Famine. Sure, there will still be jobs to be had out there but for a job on a single engine 6 seater doing joy flights, you may be competing with 10 other hopefuls instead of 3.
Good luck.