Rocky - inflamed/swollen gums

I have a visit scheduled this Monday evening with a vet that makes house calls to take a look at the gums around Rocky's upper left canine tooth. He's prone to mild gingivitis, but the area is now red & swollen. He's still eating, drinking, playing and so on, but we all know how adept cats are at hiding things from us.
I've never used a home visit vet before, but since he's almost impossible to get in a carrier, this should work out well.
I told the vet I would meet her outside and we'd come in together, because if the door bell rings, we will never see Rocky again. As it is I will need to close the bedroom doors so he won't get under the beds or deep inside a closet.
Wish us luck!

Good luck, and let us all know how it goes.

Whatever it was came to a head and just burst. It is localized to the gum area above his upper left canine tooth. I got him up on the counter and dabbed the area with peroxide diluted with warm water. We can't see the vet until Monday, so I will just keep it as clean as I can until then. Is peroxide the best thing to use?
Rocky's still eating, drinking and playing.
Thanks