Can you hurt your ears with your own voice?

The human ear has some very fragile parts.
In a singular event, probably not, but if the person’s ears had suffered damage already, their own voice could add to the previous damage.

Auditory systems are complex and have mechanisms for protecting hearing.

Mariah Carey spun a cap off a bottle with her voice & she showed no signs of ear pain. Yes, she shut her ear on the left side; however, the right ear had no protection. Although logically it “might” happen, I’ve never heard anyone claim that it has happened to them.