Is it a cold? crusty nostril on pullet, fishy smell

We brought home a young (about 3-4 months) orpington pullet on Friday. She seemed healthy, though she needs to put on weight.

We are keeping her quarantined from our flock, and she's eating and drinking well. I dusted her Friday when we got home.

I noticed yesterday (Monday) what I thought was a pine shaving stuck to her beak over her nostril. I picked it off and noticed a fishy smell. There seemed to be a watery stream but I couldn't tell if it was from the water she just drank, or if it was running from her nostril. I didn't notice it later. Today she again has something over her nostril, but again it looks a little like a pine shaving in color and size.

I did add vitamins/electrolytes/ACV to her water, and gave her some plain, homemade yogurt as well. I'm feeding her the same feed her breeder was giving her (game bird starter). I also added a little pressed garlic to her water yesterday, just in case she has a cold. The only other thing I've noticed is that she holds her tail pointing down -- like when hens roost, though maybe this is just her?

Other than that, she seems to feel ok.

Could she have a cold or something more concerning?

Thanks. I'm not sure if it is/was Coryza or not. I *think* I smelled something, but just that one time. I considered euthanizing, but about the time I noticed that the pullet had some symptoms, one of our australorps started sneezing. (I did quarantine the pullet from the beginning, but somehow managed to transmit the germs...) The pullet only seemed to show a watery discharge from her nose for about a day. The Australorp had symptoms for a good 5-6 days, and the others seem to have only very mild symptoms, if any.

I started them all on Tylan when the Australorp showed up sick. I had isolated the Australorp right away, but she never seemed to act sick, except for the sneezing. No signs of puffy/swollen eyes, and I haven't noticed the odor again.

So now I'm not really sure. Is there a way to have a hen tested?