Looking for a TV episode I saw as a kid in the late '70s?

Looking for a TV episode I saw as a kid in the late '70s:

All I can remember about it is a person (honestly don't remember if it was a man or woman) sitting before a vanity. Something about the episode lead me to fear that the person's reflection was going to reveal that they were hideously deformed or mangled, so right as they turned to look into the mirror, I looked away (I was like 7 or 8 at the time and easily scared, sue me!). So I have no idea what their reflection revealed.

That must have been the end of the episode, because when I peaked through my fingers shortly after, it showed the show's host -- who I'm pretty sure was Rod Serling. That, and the fact that the episode was in color and not black and white, makes me think it must have been an episode of Night Gallery, not The Twilight Zone. But I've read the synopses for every episode of Night Gallery and none of them ring a bell. If it was a Gallery episode, I don't believe it was the episode The Painted Mirror. My episode had a mirror, but the mirror wasn't the focus of the episode like it was on the other.

Now, there were a number of anthology shows and movies back in those days (this would be around '79 or so) so there's a chance it might have been a Night Gallery knock-off with a Rod Serling wannabe. But I'm fairly certain it was Serling and Night Gallery.