Minecraft crashes and makes me lose my world save

I was playing on my survival world without any problems. Today i entered the nether(not for the first time) and started exploring in a direction i havent been before and suddently my minecraft crashes. I open minecraft again and when i go to singleplayer i notice my world save isnt there so i check appdata(.minecraft) to see if the world was on the saves but it wasnt so now i dont know what to do or where the world is it disappeared after the crash.
The first file is the crash report and the secont one is the last save log from that world.
Pls reply when you can and thank you in advance