ProAction Shredder Problem?

I recently bought a ProAction 10 page shredder at Argos.
it was working fine until the paper started to jam a few times. I managed to clear the paper a few times and used the reverse option but there was this time when this did not work so I used a sharp knife edge to remove the excess paper from the motor (i unplugged the shredder beforehand). I managed to clear the jammed paper but now the shredder is damaged it seems that a few plastic attachment on the motor have been accidentally broken off and now the shredder is making a funny noise and only shreds 2 sheet of A4 paper before it goes again. What do I do... I spent £30 last week?