Minecraft world won't load?

Ok so I have been working on a world for a few days now, and I came across this unloaded space in the map. I thought that proceeding to go inside would fix the problem and load the chunks. But instead I got stuck inside it, to where all I could do was look around. So I quit to title and tried reloading the map and it brought me to what I'm showing you in the photo. The map won't load. I can access my inventory but I just keep slowly falling down into nothing. Please someone help me with this, I really don't want to lose this map.