Was playing on my world this morning around 9:30am est, no worries.
Tried to log in just now at 8pm est, and it generated an entirely new world and i have no items.
This is very shocking and disconcerting. I have been playing on this server with my two daughters who have invested a lot of time into this world. Please let me know if we can get this corrected. 
server address: G8kpr3000.aternos.me
Edit: it appears that my files are still located on aternos, but when i join via minecraft, it doesn’t access it.