The good news is, I've not heard of it for a disease or illness ... and I am pretty well read on them. If you think it is a scratch, you could add some melafix (which shouldn't hurt your fish if they are not injured) or just some stress coat/zyme. The female couldn't have hurt your male, although I wouldn't put it past her to try... she'd only be able to nip his fins though.
Your female is probably pregnant because that is when males bother them the most, or she's just had her babies in which case he's trying to impregnate her.
Just keep an eye on the red mark, and keep us posted. If you feel there is not an answer fast enough (please excuse me because I've got 15 credits with 2 difficult classes and a independent study - I'm nearing the end), please feel free to email me at phishie@pethobbyist.com and I will do my best to help you figure it out, but like I said, I don't think it's anything to worry about.
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Phishie
"An ounce of prevention is worth a pound of cure."