The files and content in my Minecraft world are not from my original world, but there is only one world from start to finish, and the file size of the world hasn't changed. I think it's like a completely new file has overwritten my original file. If you can please check my Minecraft world and fix it 

There is two different Minecraft world, the one is I just create it, their Mb are Differs greatly,

And the world change before  that has cherry tree, and panda  

But the world change after I just got nothing and being a different place