ew thirty or yep thirty?

I couldn’t take a shower in the morning so I did it after lunch. In the meantime, I was humming an old song ‘어떤가요’. All of a sudden I remembered someone’s saying ‘Ew, thirty’. Actually I am not 30 yet but strictly saying I’m 28. Yeah but anyway that is not that wrong. I would say ‘It’s about my preference and about the mood. Not about the age!

Is this the way we’re aging… or growing?