be above (oneself)
To be acting in a conceited manner. Primarily heard in UK. Geez, you're above yourself these days—the rest of us have opinions worth hearing, too, you know!
be/get aˈbove yourself
(disapproving) behave as if you are better or more important than you really are: She’s getting a bit above herself. She’s only been working for me for two weeks and already she’s telling me what to do!