It’s not very common, but it does happen from time to time and doesn’t always end up with a LD.
I found this post later. It’s the same kind of experience
[url]Aware that it is not real, but unaware that I'm dreaming.]
I had another one two days ago when i dreamt about a midget walking on the edge of a fence and i thought i was watching television!! 
It was, as you said, pre-lucid cuz i soon realised it was a dream! Yey!!