Haha, I've done it alot aswell.

Once, a guy (sort of like a fairy type man, thing) was teaching me how to fly. He told me that I just needed to expect and believe that I would fly.
Then I commented that it reminded me alot of Lucid Dreaming that I had been reading so much about.

And another time, I dreamt I had lucid powers, and about trying to get them to work. Actually, that has happened several times. Like not long ago, I was running downhill, repeatedly jumping, trying to fly. I wish I actually was lucid :3

But yeah, definitely possible. I think the general rule would be that if you doubt it was a lucid dream, then it wasn't. It should be pretty clear when it actually is.
(Comming from a person who only have had 1 lucid dream ever. Don't listen to me.)