There is a theory that any 'branding' marks that may have been given to you are only viewable under UV light, so that's another route you can
take.
There is a particular shape that is normaly left behind if you were branded. I'm not going to say what that shape is yet, just in case you find
something...
Some people will go to many lengths to get any hidden memories unlocked, be it through regression or hypnosis.
I prefer to wait and let any dreams I have help towards unfolding my mind.
I have tried meditation, but that in itself takes lots of practice to clear your mind and allow your mind to reflect in on itself.
My belief is, that if anything did happen, then the memories of the event will come to me in all good time, or rather, as I become ready to understand
and accept the event.
There could be a lot of other 'down to earth' reasons as to what you experienced. You'll either work it out or it'll be a mystery for a long time.