My Microsoft Account is gone

So following scenario: I wanted to do my Windows update, clicked around a bit and somehow changed my account and noticed that there was some strange Russian email registered as administrator. Before that, I was always registered with my Gmail address as administrator and never had any problems. So I tried to delete this account but because it was supposed to be the only account on my PC, it didn't work. Then I looked up and in my user folder was still my user who belonged to my account. The users name was maks which is minei. I then made a new local user in hope just getting all my stuff and d