1995 Dodge Neon Brake pedal gets hard and brakes overheat

I've got a 95 Neon that my mother gave to my daughter. Lately the front brakes seem to apply themselves. you'll be driving along and it feels like the brakes have been applied. When you let off the gas you can feel the car braking. After several miles you can smell the brakes. I've replaced both sets of pads and rotors. It is still doing the same thing.