Audi A4 problems

[Cash]

Hey,

Can anyone help me, I have had an issue with my car the last 2 days I have driven it its an Audi A4 2005 when driving down a dual carriage way it has felt like the car is pulling back almost like the car was going into a wheel spin, the revs can jump up to 7000 even though my foot is not on the accelerator. Has anyone else had this problem or know what it could be? I don't have any knowledge on cars so any help would be great 

[Magnet]

Manual or automatic Carcharel? 

Kind regards,

Gareth.