ELI5: How come every time I’m gonna to cry, I just yawn in instead?

So uh, for the last few months, everytime I’m about to cry I yawn. And maybe I cry like 1-3 tears but that’s it. Even when I’m really sad, I just don’t. I don’t have any crazy trauma, and I haven’t been stressing a lot lately.

So, why? Is there any good answer to why this happens? It didn’t always happen, just recently I lost the ability to cry I guess. Anyone else have a similar experience?