Terminal user name problem!

Hello;

I have MacBook Pro (15 inch Late 2011) and Mac Pro (late 2013)

When I use my wifi connection every time I log in to terminal

I got someone else's username appears on my screen. Am I hacked?

This is the one with the correct computer name (not connected to wifi)

This one is the one I get when I'm online (I don't have a macbook air) connected to wifi

This is the one with the correct computer name (not connected to wifi)

This one is the one I get when I'm online (Paulas-iPhone???) connected to wifi

Is there any solution for this? or can anybody tell me what that means?