Organic Chemistry is always the subject you were warned about that could potentially crush your pre-med dreams. While it does have some bearing on your potential to become admitted to medical school, you should face the subject not with fear, but with love :).
Orgo is by far the most challenging yet most interesting subject you may take as a pre-med student. As a future doctor, organic chemistry sets the stage for you to understand any drug interactions and biochemical processes that you may become privy to as a student or future researcher. Orgo is definitely the cornerstone of pharmacology as well.
While it is true, some minds can manipulate shapes and see things in 3D better than others, the distinct skill set required for mastery of this subject can indeed be learned, but only through practice and diligence. While you may have been able to slack off in Gen Chem and push studying for your exam until the night before, it will not work in orgo. You will need to study every day. You should invest in a molecule kit for building and visualizing (dorky, I know, but so so helpful). You should also have a study group that you meet with frequently, as this is subject that can be debated and should spark insightful conversations. You may pick up something someone else did not notice, or vice versa-- such as the possibility of a methyl shift, or some sort of rearrangement. In any case, it is not a subject to be read and studied quietly. Get to a chalk board and draw out the mechanisms for every problem or reaction you come across! I have even suggested to some students that they buy a mini white board to carry around for practice on the go.
Push electrons. Draw your arrows. Consider the solvent and any side reactions. Have all your bases covered, even if it seems like you are going way overboard. This is a class that needs patience and attention- just like you would give to a significant other!