Forgot most of a Lucid Dream, yet remembered 2 non-lucids vividly.

I know without recall it's easy to forget any kind of dream, including lucid dreams. But from experience I also know that lucid dreams are way easier to remember than non-lucids. This morning I was able to recall 2 long, vivid non-lucid dreams.

About an hour ago, while reading 'Exploring The World of Lucid Dreaming', I suddenly remembered a fragment of a lucid dream I had last night. I was flying, with perfect control. I wrote the fragment in my DJ, and about 15 minutes later, another example in the book made me remember yet another fragment from the same lucid dream I had last night. About 10 minutes ago I remembered yet another fragment from the lucid dream.

So, I was able to recall 2 non-lucids, vividly, with details. However I'm not able to remember the lucid dream I had last night. I just know I had a lucid dream in which I flew, I sat down and looked at my hands to stabilize, and I tried to summon my 'Time Dilation' watch to extend the dream time.

It's the first time that I can't recall a lucid dream with details and vividly, and I find it odd. I don't even think it has to do with my recall.
Has anyone experienced something similar :S?
My only theory right now is that the lucid dream occurred during Non-REM Sleep, in which we have short dreams, not as vivid as the ones we get during REM sleep.