college courses as a high school student... help!

<p>Hi,
I'm currently a high school junior and have taken three county college courses on my own time (most of them were summer courses) that pertain to my intended major. I did pretty well in those courses (A,B,A). However, now I'm taking a fourth course this summer and there is a high possibility that I will end up with a C. These courses are not factored into my high school GPA (they have nothing to do with high school at all) - I took these courses to familiarize myself with topics I might want to study in college. How would a C in a college class the summer before my senior year affect my chances at a top school such as NYU Stern? i'm getting very nervous about this.
Thank you!</p>

<p>Please repost on the NYU forum.</p>