username and skin changed without my knowledge

I logged on to my minecraft account today for the first time in about a month, I noticed my skin was weird, and when I typed in chat the name was 'explored1' even though my account name was 'rpminergabe' and I had never changed it.

I went to Minecraft.Net to fix my name, and when I clicked to change my name, it said I had changed my name on the 23rd of December and I haven't used my account or used minecraft or changed my name at all since at least early december, the 10 at the latest

 

I would like to change my name back, as I dont know what happened, it also changed my skin, so I am worried that my account was hacked and I'd just like to be able to change my name back to what it was. I dont know what to do if it was hacked, I'm just 14 I have never had to deal with this kind of thing before so I don't know, I just want to change it back and my skin if you could, thank you.