My world just got deleted

I was just playing earlier today on the server that I have been using for months; I leave for an hour and when I come back to start the server again, I enter and it's a new world!? What happened?

I was not using a backup (I know, it's "my" fault), I just started using plugins as well (PaperMC with EssentialsX and LaggRemover), I don't know if I should blame them, because I have lost progress once before using the plugins. What do I do? How can I recover the world?

I was playing on 1.14.4 btw

I'm not sad for losing the world, just disappointed honestly.

Aternos hasn't been great for a while now with constant lags and disconnects; I can't build mobfarms because it makes the server TPS go down rapidly with just 30~40 mobs in an area, can't explore the world and can't even mine 'cause once I go on new chunks (or other player does) it lags like hell with constant rollbacks. All in all it's not enjoyable anymore.