Just some observations here....did you ensure you met the Pre req GPA requirements to apply at each of your schools? Did you meet the GRE requirements? I think the pGPA and GRE scores are maybe more of a factor than cGPA. Bad grades aside, if you can't get high grades in the pre reqs, the school's see someone who may not do so well in a very tough and heavy science curriculum.
You may benefit from getting straight As in a heavy academic year, and then applying to schools who look only at most recent. Every school uses different numbers. You may want to be strategic...ie don't apply to schools with GRE minimums, or apply to schools who take the best grade of pre reqs.
Don't give up, but be open to the critical admissions eye on your stats. (Took me 2 times applying to get in...and the second time I only got in on wait list. I had a horrible CGPA.BUT, I retook every one of my pre reqs for an A so there was no question I could do the work).