Gosh, they are a lot of questions Mr Merlin!
My relationship with mine is straightforward and much more simple. I know he is mine because he was sent to me and we get on and he stays close.
Dragons are normally with you for a reason, try to find out why it has come to you.
As for whether it is real, try asking it some questions or noticing what it does; if it can tell you things that you couldn't possibly ahve known, then it is real as far as you can tell. Take a look at my Dragon Tales in Cryptozoology - these are TRUE stories and incidences that finally convinced me that Dharma is real. As to whether he is a real part of me that is very psychic or a completely separate entity, that I cannot prove, only to say that since he was an unexpected arrival and I did not believe in dragons prior to this, then that makes mine real to me.
As for your impressions and sensations, make a good note of them and watch for patterns, this will help you sort out impostors from your own; there should be a signature movement or signal that yours always gives you that will show you who he is - a bit like an identity card.
Exciting isn't it (IMG:
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