I'm pretty sure it wasn't a true reflection, since he reached with his right arm too, just like me. In a mirror he would've reached with his left arm. It could be posible though, that it was my subconsciousness, with whom I always "talk" to as a person, when I go to sleep.
The shared dream sounds a bit spooky I'm not sure how people experience those dreams.
But yeah, I've never felt something like this in a non-ld. It was quite an experience.