I hate to go a bit off topic, but over here in Australia going from high school to university is like going through the desert to find the oasis. I love uni simply for the fact that every pain in the ass you knew in high school was too fucking stupid to ever get into uni.
I know at the start of this thread you were worried about your grades, dont ever feel too bad about them because ALL of us go through this. I dont know if you get this but over here for some results they just post all the results by our student number, and you can see what others got... always makes me feel better that I am never the lowest score
I gotta repeat an elective over the summer because I failed maths (stupid differentiation) but trust me, the feeling of failing a subject or two is nothing compared to the feeling you would of had if you hadnt ever tried in the first place
Parents are great about this stuff, as long as they know you tried hard they wont be dissapointed in you, because over the course of their life they might have missed a potential chance at maybe a better education or better job (promotions).