Traffic ticket in VA question: Should I fight this in traffic court?

I got my first speeding ticket in 17 years (38) for 69 in a 55. The very young officer demanded my lic and reg and told me I was doing 75...I told him that was ridiculous....he told me he clocked a vehicle meeting my car's description with a driver in a dark shirt making a (90 degree) turn at the last intersection at 69 (not sure what happened to 75??)....I told him that's not even possible and there is no way it was me. The officer was doing 55+ going the other direction & apparently had to make a u-turn so I was stopped 3.5 miles and 3.5 minutes @60mph past the alleged intersection based on the color of my car by an officer who observed a black car from across a divided highway doing 55+ in the other direction. Should I fight this in traffic court ? I am scheduled for a business trip to AK on my court day, can I get a continuance ? Thanks in advance.