Electrical problem
2003 Ford Mustang 6 cyl Two Wheel Drive Automatic 34000 miles

I've just recently had my battery changed a few nights ago. My car would not start so we tried to jump it and it wouldnt work. So i went out and bought a new battery and had it installed. the car works fine but now my radio wont turn on at all. None of the radio lights or buttons work. Car works just fine, runs good, lights work (both interior and exterior) wippers, head lights, etc. dont know what to do??