You need to ask the schools about their policies. Usually most like to see prereq courses done within the last five years. Have you done anything to build on your courses or degree?
I graduated with my BS in 2014 and haven't done any courses since. I met with my top school before starting the shadowing/mcat process and they didn't have an expiration on prereqs. I got secondaries from all the schools I applied to and have gotten 2 A and 1 WL this cycle. So there are definitely schools that don't put a lot of weight into your graduation year.