Do gas pedals go bad?

Out tinkering with car, I push gas pedal (65 Dart) all the way down and it stuck! So then I proceed to push it up & down and it sticks when all the or almost all the way to floor. I put a little grease in back where pedal and rod rub that didn't help. Have no idea how long it's been like that, just cruising it would be fine but if you floored it, it could stick, not good. Do pedals wear out and are there new ones out there to replace it. thanks