Rat URI help

One of my rats has started making a similar noise to what I've heard on YouTube as an example of a URI. I've immediately booked her in for a vet appointment but the earliest I can get is on Thursday morning. It doesn't sound as bad as the one I heard on YouTube but obviously I wanted to double check with the vet.

Has anyone got any advice on what I could do that might help until Thursday morning? Xx

Edit: she's still eating, drinking, running in her wheel, chittering and chirping as usual. I also can't see any discharge or anything around the noise/mouth yet, it's literally just the slight noise.

This is the link for the YouTube video I've used as reference: https://youtu.be/21-pn5KRY-A?si=LfUHjFlOgJogduyY