Hi, not sure if this was a movie or TV show. All I remember for sure is a moment where someone is standing in front of a mirror, and then, I think because of some kind of evil force, the mirror starts bending back and forth somewhat and then shatters, and a shard of the glass flies into the person’s chest, killing them. Thanks!
Death Spa (1989), @ 01:19:00?
If it was in black and white, it could be the Thriller episode, The Hungry Glass, starring William Shatner.
Way of the Wicked (2014)?
https://www.imdb.com/title/tt2483208/
You can see the mirror explode at the very end of the trailer.