Speeding ticket court?

okay so a while back i received a speeding ticket. The thing is i know i wasn't speeding, but im not sure how i can prove this. Heres the situation. Theres is a small mound/bridge and the sheriff was behind that bridge driving towards me. I was heading towards the bridge at 55mph ( the speed limit there). A car ped me up speeding and was in front of me thats when the officer came over the bridge and the guy that ped me up slammed on his brakes, i just kept going at the same speed then i saw the officer turn around and start following me he pulled me over right before crossing the bridge. What the officer didnt see was that the car in front had ped me up and i really doubt he could have gotten me if the car in front of me was pretty close to me because he had just ped me up when the officer ped both of us. I think the officer just pulled me over because i had a much nicer car, i had just put a body kit on it and got 4th place in a car show... I think my story might be a little hard to belive considering i am 17 years old I've been pulled over at least 6 times and its always the same bullshit "you were driving aggressively or i saw you swerve and had to make sure you weren't drunk" this is the only ticket l have. I know i don't drive like an idiot racer and I really cant afford a speeding ticket especially now that I have college coming around the corner.