How do you know when you’ve blundered?

How do you know you blundered?

You either lose some pieces or directly lose the game.

Or both at the same time.

I have a feeling it happens more to her opponents than to her personally.

Why?

Trust me, you'll know. If I had a dollar for every time I have played a move and immediately cringed, I could probably make enough to live off of just by playing consistently.

Blunders usually become apparent fairly quickly. Many of them are either miscalculations or a failure to diagnose a threat. Of course, every once in a while the opponent misses the blunder, in which case you'll typically either breathe a sigh of relief or laugh about it later when you find it during analysis.