won't rev over 2000

Hello,

wonder if someone can assist had this weird issue this morning and i wonder if its to do with the cold weather as i was on my way to work the car would not rev over 2000 revs so i stopped and decided to push the accelerator pedal all the way to the floor heard a slight clonk and everything was back to normal again and i drove 52 miles to work without any issues is this a sticking or seized cable i wonder ?

2000 renault laguna 1.9dci

thanks.

won't rev over 2000