Really? It doesn't replace the old grade or anything?
Because if you re-took the class at the college, the new grade often replaces the old grade. Sure, you can see it on your record but it won't affect your gpa.
First off, your school's calculations of GPA don't matter one bit. It's AMCAS that does the calculations. Second, get that GPA up. The average to be accepted is a 3.66 as of last yr and it's been rising, so don't sit back just yet. You need to achieve, achieve, achieve from here on out!