I don't think so. Fire flies glow on and off, and don't come to a complete stop in midair. Plus, this thing was very far away.
I have hiked Deer Mountain in Rocky Mountain National Park before dawn in order to see the sun rise over the mountains. I saw the same thing you described. As the first hints of dawn started to creep into view, I realized I was seeing other hikers who were going up Long's Peak and were screwing around with a flashlight. They may have actually seen our light and were trying to signal us. The thing I noticed is that the light contrasted with nearly uniform darkness surrounding it gave the appearance that it was floating.
I have no idea if there were any mountains or hills near you, and I'm not saying that's what you were seeing, but it sounds very similar to my experience.
That was an eerie hike. We were walking up to herds of elk that were bedded down not 20 yards from the trail. You would suddenly hear lots of movement around you and then need to flick on the flashlight. Yes, I had a gun on me, as well as bear spray.
The creepiest one I ever had was a particular hike on a fairly distinct hill top. It was a seven mile round trip hike from where I parked, to the peak, and back. When I was about a mile from my truck dusk was well underway and I started getting a weird feeling and felt compelled to look over my shoulder a lot. When I was about a quarter mile from my truck, I had a very strong urge to look over my left shoulder. As I spun around, it was just in time to see a brown head of some sort of animal duck down very quickly behind a large juniper bush, out of reaction to my very sudden movement.
My first reaction was that it was a deer or young elk,
but the ears of the brown blur looked too short. So I stopped dead in my tracks, drew my FNP45 because we have A LOT of mountain lions in my area. I assumed I had seen a deer, but wasn't sure. I expected to see one running off in the opposite direction since I'd obviously spooked it. Once you spook a deer or elk into moving, they run flat out and don't try to hide. However nothing was seen running away, nothing at all. A stalking lion or even just one that is curious would be more likely to crouch and hide, as it is the natural instinct of a hunting cat.
I walked slowly towards the juniper bush to get a better look, but my better sense took over and something told me that I was pushing my luck. I literally walked backwards the final quarter mile to my truck with my weapon drawn, cocked and locked. To this day I don't know if it was a ninja like deer, a trick of the light and a case of over active imagination, or if there was a lion watching me from the bushes. Part of me wishes I'd found out. The other part of me acknowledges that at dusk, the forest is the lion's domain, and I am a visitor. Best to not overstay your welcome.