You did the right thing changing your password. I don't see how anyone could actually access your account without knowing the email and password which I'm sure you would never give out to anyone.
I don't believe that the other person was actually going to do what they said, file a complaint against them on your console. If you do decide to raise the issue with support they could well lock your account totally until the investigation is completed, that means even you couldn't access it.
It's your choice of course in what you do.