Last night I was in my bed around 11, I was relaxed and thinking to my self: "I will remember my dreams, I will become Lucid."

I used a technique I got form a friend where you hold your arm in the air, like just propped upright from how you're laying, then when you start drifting asleep it will fall and wake you up. After about 15 minutes or so the arm dropped once and soon after I felt really odd, like numb-ish, then my leg started to twitch a little and I could have sworn I might have saw flashing lights. But then I noticed what was ahppening and I got real excited and then stopped being so relaxed and I could tell the feeling was gone. I just went to bed after that experience and woke up in the AM to TRY and record my dreams which I am having SEVERE difficulty with. But thats another story. My question is, what was happening then?