First Asalamu Calaykum.
Second slow down!
There is no need for you to contemplate abroad for school if you are in the U.S.
FIrst you are in highschool. SO it is not the end of the world. If your destination is MEDICAL SCHOOL understand now high school is the last thing they worry about.
However, what you seem to be worrying about is undergraduate university degree. Let me try to make you understand couple of things.
Colleges in the U.S look for and are especially sympathetic of UPWARD TREND. People understand not every student's situaton is the same and not every student is going to start out at the same. Which is why they look at upward trend.
What is upward trend?
Upward trend is starting out bad or even real bad and exponentially rising in terms of academic achievement.
SO you are a D student freshman year, sophomore you are B almost B student, and junior year you achieve nothing but A's.
WHen your CUM GPA is tallied, it is not going to be so high. But when your individual years are analyzed you have a very distinct upward trend which can give you extra points ever a person who has a 4.0 cum gpa.
THis is because it shows determination, hardwork, and perserverance and most colleges want to retain students so it shows you have capacity to overcome difficulties and rise above them.
As long as you continue in this manner, you should be fine especialy if you are making A's in junior year.
As for medical school, your high school record has no bearing. It is your college record.
Hope this helps!