Sounds like you were there, it's hard to say because SP varies so much from person to person. I experience SP very often, and have getting there down to a science where I can pretty much do it on command. I've had some VERY intense SP exp's that scared the shit out of me ( one was a hallucination of someone shooting a gun RIGHT by my head, and hearing the loud bang... )

Before entering a deep SP I feel this " warming sensation " go over my body in "waves", almost like I can feel each wave start a my head and work its way quickly to my feet, and every time I feel a wave of warmness I get a bright flash hallucination... pretty cool.