Meditation question...serious meditators only please!?

Ok, about a year ago, I was meditating and got a freak vision, except more... I was concentrating on breathing, and next thing I know, I got a weird feeling in my eyes almost like looking at black water that was rippling. I passed through the barrier and opened my eyes and (I kid you not) I was on a snow covered mountain and could see another peak. I felt sensations like snow on my feet, wind in my hair, and I felt cold air in my lungs. (The place I was in was the exact opposite of what I felt,so I don't think it was outside stimuli.) Before I could do anything, I felt another sensation in my foot that broke my concentration. Turns put my foot had fallen asleep. THIS WAS MY FIRST real time meditating. I've tried to replicate the process, but when I get to the ripple barrier, a fear stops me. IF anyone's done this before, please answer these 3 questions:

1. What exactly happened, was this my minds interpretation of itself?

2. IS it possible to get back?

3. The fear that stops me, is the thought my mind will become trapped their, is that likely or even possible?

Please note im not crazy. Ive heard of a similar instance before with someone else.