Withdrawal from 3 courses and C's

Hi. So I go to Northeastern University but I was accepted into the NU i.n. program. If you don’t know what that is, it means you spend your first semester abroad on a pass/fail basis. Because of that, no one really tried to get good grades because it was so easy to pass, it was more like a gap semester. But now coming back, I ended up having 3 C’s, withdrawing from a course, and now in summer I am taking two classes but it looks like I’m about to get C’s again and I really don’t want to kill my GPA anymore so I would like to withdraw from them. I know I messed up and there’s no excuse for that but this particular summer semester I got into a jet ski accident and missed a lot of school because of it. I am trying to do premed and my GPA is already a 2.3 and I know it’s my first year and I’ll have to really kick ass for the next three years but I want to know what my shot is. And my shot for business school as well. Will these withdrawals really kill me? Should I take the Cs? I’m really lost and I know I screwed up but i need to know if there’s any coming back from this and what to do… I slacked off because of my jokes first semester and now I’m realizing what a huge mistake I’ve made and I’m ready to pick myself up. I did well in high school with a 4.1 weighted GPA and an above 2000 SAT. I know college is different but I know what changes i need to make to improve my grades from the semesters onward but I know medical school is extremely competitive. i’m not sure how competitive getting into business school is but if I went that route I would like to get into a better school like USC or something, not just any school.