spawn in end after going through portal but no damage.

I went through the ender portal in one of my friends worlds that I always play on, but i was stuck on the building terrain screen. I decided to quit minecraft because it wouldn't load. When i loaded back in i somehow spawned in the void, 700 blocks from where the end island is. I did a test in another world and found out somehow the glitch was keeping me alive in the void. Than i played on a copy of his world and found out i could move at the bottom of the void, so I made my way back to the main island in the void and i found out if I got to close I would start to take damage. So want i want to know is how this glitched happened and is there any way to get out of the void. I haven't done anything in the orginal world yet because i am too scared to. [ I already tried flying out]