This is day two of Victoria seeming like she's going to hairball but not following through. Like, off and on all day. She's doing the "hhkkk" sounds, and sometimes it looks like she'll get a hairball out, but no dice.
Internet search says maybe asthma, but no, she's not wheezing. Or maybe respiratory illness, but the internet seems certain that other cats in the house would be symptomatic as well, and they're not.
She's otherwise acting totally normally, including purring.