I'm positive it's nothing. The Park button is basically an electronic parking brake for the front wheels. The actual electronic parking brake locks the rear wheels. I know the manual mentions you cannot shift into reverse if moving forward too quickly, nor the inverse, and I'm sure it'll ignore a parking button push at > 5 mph. However it probably will allow pulling up to engage the actual electronic parking brake, but that's merely the same thing as pressing the brake pedal hard (except on the rear wheels only); it shouldn't damage anything unless you get rear-ended.
