Fiat Punto juddering

Hi guys, car passed mot last week and last night when driving home i suddenly noticed the car juddering and bouncing movements on the clutch, there seemed to be some rattling nocies coming from the engine as though a chain or something had come off, any ideas the car starts up no problems and revs no problems however when you start to drive the noise is still there only when accelerating, when you are not accelerating its fine, any help appreciated and how much am i looking for at repairing at a garage