Restarting issue with my world - please help me

[TavinMC]

So basically, I wanted to add a wand to my server and also change some things like the view/draw distance and how many players and things like that, then it told me to restart my server, so all the things I've changed can save. After restarting my server (which from what I know, only restarts your world when you apply changes and doesn't delete anything, the deleting happens from resetting the server) I went into my server as usual and come to realize that my whole inventory has been wiped clean, and I'm at, what I think is spawn based off of my memory and there are crafting tables and signs that it isn't a new world. I'm still quite concerned and scared that maybe I did something wrong, although I know for a fact that I pressed the red restart button at the top of my screen on the website, and have ruined my world that I have put many hours into. 

Please can someone help me, I have been trying to figure out what has happened, I've searched many different things and only some have come up, but with no answers. I am just looking for an answer on what I did(if I did something wrong) and how I can find my house because as of now I am in what seems to be my world, but it's as like I did actually reset my world. - Any help would be appreciated.

By the way, I have tried restoring my world from when I made a backup before this incident has happened and, idk if its just glitched or there's an issue, but nothing has happened.