OP, I regret to inform you that you will not be competitive for any United States medical schools (DO or MD, to be clear). Based upon the provided information you will most certainly NOT qualify for any of the aforementioned national institutions and should therefore be prepared for the repercussions which therein follow.
I suggest stocking up on sunscreen and getting some color because you're going to the Caribbean. There are forums here on SDN which specialize in special cases like yours. I recommend brushing up on that literature - better yet, memorizing it because you will, rest assured, need it.
Best regards and good luck on your journey,
-Captain Ahab.
PS here is some dermatologist recommended sunscreen you can buy in bulk, for a relatively cheap price. This brand can be found at most merchants, nation wide.
The good thing about Banana boat is that it's SPF 50 and utilizes patented "spray on technology."
Once again, good luck, God bless, and God speed.