The degu is sniffling and sneezing, but seems fine. Is she sick?

Hi everyone, I'm a bit worried about one of my three degus. She had a cold once before with her previous owner. For some time now she's been sneezing more often and sometimes grunts a little, as if her nose was slightly blocked. Half an hour ago she started sneezing almost continuously and it sounded a bit strange. I can't describe the noise, but I wouldn't say it came from her lungs or airways directly. Things are a bit quieter now, and I can't hear the noises from before anymore. She's eating, is active, running, drinking and playing with the others. It's just the constant sneezing that's really worrying me. Her eyes and nose look completely normal, no discharge or anything else. She's been given different food since yesterday, and I suspected that she might be allergic to something and that's why she's reacting like that. I don't have any known allergies so far.

Is it an emergency? Tomorrow is a holiday, and my vet isn't supposed to be back until Monday. Only the animal clinic can take emergencies. Does that count? I'm incredibly afraid it's more serious than it seems, but I don't want to subject my animals to unnecessary stress. Besides, they're not exactly tame, so it will be difficult to keep them.