First, according to the AAMC website, the averages for people who matriculated to medical school in 2008 was 3.59 BCPM GPA (biology, chemistry, physics, math), 3.68 overall GPA, and 31.2 MCAT.

Your GPA falls way short of that number at the moment, so you are going to have to spend some serious time improving your science GPA. You should seriously consider getting a second major in a science field so that you can increase the number of classes in your science profile and thereby (hopefully) raise your science GPA to the mid-3 range. You have to dazzle them at this point if you have any hope of getting in. To see what numbers are being accepted at the various schools nationwide, go to student doctor network and click on applicant profiles. I warn you, it will be disheartening at first. Look for the ones that inspire you, and there will be a few of those. There are cases of low GPAs getting into medical school. See what their profile looks like (probably a solid MCAT, great clinical experiences, and they applied early). Just keep in mind that if you want this as much as you say you do, then you’ll get there in time. And by graduating at 19, you have a little time to boost your profile.

In the event your undergraduate experience doesn’t improve enough, you should consider going into a post-bacc program (such as the one at Georgetown or Drexel) where you get a year to prove your viability in medical school. It’s sort of an all or nothing year that you hope will prove to adcom folks that you can make it in medical school.

Also, your MCAT is going to have to be GREAT! Let’s say you manage to get your science GPA up to 3.2, you’ll need a 36 on the MCAT to become a “close to average” candidate. You should consider picking up some review books now, as they could help with school and give you a head start on the MCAT. Only use the best (Exam Krackers for biology and verbal and Berkeley Review for physics, general chemistry, and organic chemistry, according to the consensus at SDN). When it comes time to prepare for the MCAT, take a review course that specializes in the MCAT. Get help in these areas!

And as J mentioned, by all means get tutoring. It’s how most people get through their premedical experiences.

Just keep plugging away and you should be able to recover to some respectability. Also consider applying to DO schools as well as MD schools. And you probably don’t want to tell people “I don’t want to go to a Caribbean school” in the same post where you say “I really want to become a doctor more than anything”, because the two statements contradict one another. Adcom people pick up on those things.
References :
http://www.aamc.org
http://www.studentdoctor.net
http://www.berkeleyreview.com
http://www.examcrackers.com

“Your entire academic history is likely to be scrutinized when you apply to medical school. If your baccalaureate degree was weak, even a strong post-baccalaureate performance may not be sufficient to overcome past performance given the highly competitive nature of medical school admissions.”

You, absolutely, are going to have to repeat the courses in which you performed poorly and here’s why: Every medical school receives thousands of applications and the admission committees want to treat everybody fairly, yet they do not have the time to review each application before making a decision. What each school does is extract the following pieces of information (overall GPA, the GPA in the prereqs and the MCAT scores) and puts them on a spreadsheet. They have already determined they are going to interview X number of applicants (usually 3 to 4 times the number of available seats at the school) and offer interviews to those applicants. They will review the application package of those applicants in depth.

The grades you have indicated will knock you out of contention. Any upper level coursework, even if done well, won’t be taken into consideration. That first cull is simply a numbers game, so you have to be competitive in those courses. For example, you could have a 4.0 GPA in your Major’s courses and a 3.0 GPA in the prereqs and odds are, you won’t make the first cut. So, bite the bullet and plan on repeating those courses.

Here’s another reason: Your Major (psychology) is known for being the easiest undergrad degree to get (i.e., not very academically challenging). People with psych degrees do get accepted into medical schools, but they have to have excellent GPAs and MCAT scores to prove they can handle the rigors of the medical school curriculum.

And a final reason to repeat the courses: the MCAT. The MCAT assesses your knowledge of the prereq course work–not upper level courses.
References :

The average overall GPA of students admitted to US med schools last year was over a 3.6. The average science GPA was a 3.47.

One of the things I want you to consider doing is taking some extra, upper division science classes in the sciences you did poorly in early on. Yes, med schools only require 1 year gen chem and 1 year organic chem, but you didn't do well in gen chem. You need to make up for that. Don't retake those classes, but do take an extra upper division chem class or two, and ace it.

Your bio grades also aren't particularly great. So I'd have you consider taking an upper division bio class or two, and ace it.

Not only will this increase your science GPA, but it will also act as your second chance, allowing you to prove that you really can get very good grades in your sciences.

This quote is from Johns Hopkins, to support what I'm saying:

"Students who do not perform well in their early science courses, but still wish to pursue a medical degree, can take additional science courses to strengthen their academic records and become competitive candidates. An average grade in a prerequisite course can be redeemed partially by a good performance in another course which demonstrates competence within the same area."

I am strongly advising you do consider doing this. Otherwise, I'm not at all confident that you'd get into a US med school – or a good Caribbean one.

I also strongly encourage you to call on help, if you see that the grades you're getting aren't what you need. In other words, get a tutor.
References :