First, how do you KNOW the person you spoke to was actually a detective and not someone faking it?
Second, there is nothing preventing anyone from framing you. However, to convict you of a crime the state would have to prove beyond a reasonable doubt that you did what they allege and that will generally require records from ISPs showing logins, access, etc.
It is unlikely they will prosecute you for hacking into someone's account and changing their status. It is simply not worth the time and effort to pursue. But, while it is unlikely, it IS possible.
So, if you find out that the police really are investigating you for this then you need to speak with an attorney ASAP.

