But I was a teenager, and would be more than happy for anyone to convince me that it was somehow all in my head :)
It was all in your head. You were not actually a teenager but a tween. Your ovaries were kicking into overdrive and you were fretting about boys and breasts. I have yet to meet a tween who was not even just a little bit screwed up. There is no paranormal. If you could provide one tiny fragment of irrefutable proof that there is a paranormal reality (like a planchet moving with an apparent gift of spelling moving all by itself) then you would be wealthy and famous. All in your head.
Happy?