My game thinks I am a new player and removed everything I worked for.

I have been playing a solo world, building anything the came to mind in survival. I had just gone to the nether and started gathering wither skulls and blaze rods. I then made an ender chest to store my valuables, enchanted tools, diamonds, and even the beacon I just crafted. I saved and quit and called it a night. I woke up today to absolutely nothing in my hotbar aside from an empty map. I was a new player in the world's eyes. My ender chest was cleared as well. However, my home, farms, and builds all seem to be exactly the same and my real chests are still full. I refuse to go to creative to get my things back, but I also dont want to grind another full day to get it back.