Wow that's really interesting...that's how I had my first lucid too (during a nap) and I didn't even know what it was. Then I used to get them everyday when I would take naps in my dorm room in between classes. Try it if you have time. It usually works for me even still. I call then unintentional nap induced WILDs.

Also, to better increase your chance of recall try setting your alarm for 5 hours after you go to sleep, keep the journal by your bed so you can write everything down as soon as you wake up.