I just remembered a dream I had when I was younger. I don't remember much of the details, but I know I saw my mother sitting in her room with her back towards me. When I called her, she didn't respond, which I thought very strange. I pinched myself to see if this was a dream, and I didn't feel anything. I thought, 'This must be a dream'. As soon as I thought that, the dream collapsed in a cacophony of sounds (sounded like bells) and the image turned black with a few gray spots, and I then I was sitting in my bed sweating, as the sounds came totally without warning and scared me to death. Why would this happen as a response to attaining lucidity? And has anyone had a similar experience?

(On a more pleasant note, this brings the total number of accidental lucid dreams that I can remember to 4! Yay me!)