Upon pulling into my driveway my brakes made a loud popping noise and I lost all braking power. Upon inspection I found my front right pads had popped out and vanished.

My only question is, why does my left front side not work now?

 

Because there is no equal pressure. If you were to pump the brakes until the piston rubs the rotor they would work but doing so would ruin the caliper piston and the rotor.

 

sounds like you lost your retaining clips..though the pads should still be in place without the clips..you would just have brake squeal. i'm suprised the caliper's piston didn't extent too much and pop out, spewing brake fluid and dumping system pressure.. either way would be a mess..