Sounds like something's up with the clutch if it's the clutch pedal vibrating/moving.
Maybe you've lost part of your clutch and that's thrown it off balance or something?
What clutch you got?
Saying that the clutch pedal is only connected via a flexi line so shouldnt move because the clutch is. Maybe that's loose and moving beause of the vibration.
Daniel james on here had a similar issue recently and turned out one of the cv's where dry.
He bought a brand new shaft that he may want to sell. So if your driveshafts are goosed contact him for a brand new one.