This topic has been covered atleast a dozen times...
NC State is a very good school, especially research wise. While I always thought of it as an engineering school (when compared to other UNC schools), they do have strong science programs. Just because its a state school doesn't mean its subpar-- especially when it comes to NC State or UNC. And its not completely unheard of for individuals from no-name schools to get into harvard med-- and NC State is hardly a no-name school. Just make sure that you keep your grades up, stay involved, volunteer, study something that you're truly interested in and passionate about, and make sure that you, as a candidate, stand out from every one else. No one can get into med school on school reputation alone, so that should be the least of your worries. You have graduation to look forward to.
As far as your high school grades go, most med schools (correct me if I'm wrong) don't consider them, so think of college as a fresh start... college isn't going to be easy, but if you are determined to become a doctor, you will.
What are your reasons for wanting to go to Harvard Med? Like jbj said, harvard isn't the only good med school out there... Even going to Harplunkit School of Medicine will result in the same M.D. Both college and Med School are what you make of it... If you want an Ivy League education at NC State, work at an Ivy League level, put forth 110% and you will be just as well off as anyone at Harvard Undergrad (perhaps even moreso). Same thing with med school.