Did you ever have a moment of sudden awareness, and it wasn't fun?

I’m thinking of something like when you have a headache. You wander around doing what you do, and your head stops bothering you. Suddenly someone says, “How’s your head?” Instantly, your headache is back. I hate this, and the worst part is you can’t get angry at someone who is only trying to show concern.

Does anyone else experience this? Can you give an example? Is there any way to avoid these kinds of things? If you know that someone has a headache, have you ever stopped yourself from asking because you don’t want to draw their attention to it?