Im a 28 year old male, I have been clean off of a heavy IV drug use that included a lot of meth. Recently, on several occasions, while laying in bed attempting to fall asleep all of a sudden I experienced a startling sensation in my head that I would campaire to getting hit in the head really hard, I hear a Pow! in my ears and a flash in my eyes fallowed by a short tapering ring in my ears, it startles me and I am suddenly wide awake again??????????