I want to become an ob/gyn?

Well first off. You should focus EXTREMELY hard on scoring well of the SAT and hopefully that makes-up for your bad grades. Other advice I would suggest are to try and take as many AP(Mostly) and some Honors classes as possible while your in high school. Try and stay away from regular classes because you want to show colleges you rank among the top percentile of your school. Most Importantly, you need to get into good medical schools that are known around in the US and not just go to your local or in state colleges. Ex: Duke, Wake, etc;