Don't feel bad at all. Your grade is a lot better than mine when I first took it; in fact it took me 3 times!! My first time was an F. I was a fresh 18 yr old college student and not quite focused. I also wasn't utilizing my classmates for group studying and I HARDLY studied. My second time was a D. I had a study group that was good for the lab but not for lecture. Then finally after seeking permission to retake the class for the THIRD time, the advisor told me I had to pass this class otherwise my financial aid wouldn't cover for it anymore. So I had me a great study group for both lab and lecture and I also studied my butt off and pulled out with a B and I was 4 points from an A.
Honestly, I think it's about taking full responsibilities about your studies. You can't leave it up to someone else to study for you. All though I lucked up with an awesome study group, I knew I had to be the one to put forth the effort to get the grade I wanted.
Now, I'm 23 and I was chosen as an alternate for a local RN nursing program that I'm praying to get into. So don't feel bad; You get what you put in! Good luck! :)