I made C's in both O chem 1 and 2 and I'm sitting in my 9th quarter of pharmacy school right now. You'll be FINE. Just work hard in all your other areas.
Ummm, ok. First of all you are at Cornell. Second of all you are at Cornell.
Ad Coms may have been concerned if you had received a C- in organic chemistry at a community college, but I think you're in a different boat all together. Would it look good on your transcript to retake the course? Sure. Is it of utmost necessity, I don't think so. If you can show Ad Coms that you know your chemistry by doing well on that portion of the PCAT, I think you will be just fine. We are all human, not everyone can be an expert at every single science discipline offered at university, and I think most people can attest to the fact that organic chemistry is not an easy class (this includes ad coms).