Anyone care to explain?

I was in bed, some nights ago, just relaxing. Suddenly a flow of energy rised from my feet and banged me in the back of my head. I was almost pushed out of my body, for a 2-3 seconds i was out, but i was able to feel my heart beting very very fast, maybe 200-300 bpm and i was back in my body. I had a feeling of floating next to my body for 30 minutes.
What was that?
Thank you