2000 Ford Focus IS IT THE BRAKES

I WAS DRIVING TO WORK AND MY CAR STARTED TO VER OFF THE ROAD IT FELT LIKE THE WIND WAS BLOWING BACK AND FORWARD. THE I STARTED TO HEAR LITTLE SCREACHING SOUND FROM THE BACK. WHEN I WAS COMING INTO WHERE I WORK THE BRAKE PEDAL POPPED BACK AT ME AND WHEN I WANTED TO TO PUT THE EBRAKE UP IT WOULD GO UP HALF WAY. SO I WENT AROUND TO CHECK IT OUT WHEN I PARKED AND THERE WAS A SMELL COMING FROM THE BACK OF THE CAR.....HELP LET ME KNOW WHAT IT IS OR IF ITS SAFE FOR ME TO DRIVE HOME