1999 Vauxhall Vectra Help!

Engine Mechanical problem
1999 Vauxhall Vectra Two Wheel Drive Automatic 153000 miles

I was a stupid woman, I took my son to watch fast and furious, he suggested I tried to drive like they do! I thrashed my car etc. And the next day my car revs between 1000-2000 revs without accelerator pressure, as tho its stuck?The rev counter rises and falls between 1000-2000 continuously? It is using more fuel obviously, and sounds when at traffic lights like I want to race everyone, I need to fix this myself as am a single parent and cant afford the garage prices. Any chance someone could tell me what to do please? Thanks Ann-Marie xx