Shifter bushings are easy to check out if you get under your car. If you car is older, and higher mileage then its a small possiblity. Yes it could be your tranny fluid hasnt been changed especially if

1)you've owned the car since its conception and have never had it changed before
2)you've owned the car, its high mileage and you have no idea when its been changed last.

Like Chris said, flush it out, then refill with Honda Fluid. Its even possible that it might just be low on fluid as well.