You’re clearly off your game. She subtly...

Asks if you’re okay, listens for a minute, then says, "Well, hope it gets better!" Tries to distract you with a funny story or a change of topic, her eyes full of concern. Slips you your favorite candy bar later with a note: "Thought you might need this :)" Doesn't really seem to notice, or just gives a quick, "Rough day?"