However, since then, one of the boys is breathing really loud. I normally can't hear them breathing at all. He almost sounds like he is congested, and he also is sneezing a little bit. In addition to the change of that hay, I also want to mention that the weather here changed really dramatically today. It's been 90F + and sunny, and today it was 60F and raining. My guinea pigs live inside, but you can still feel the change.
I should also mention that the brand of both the timothy and orchard grass hay is Oxbow.
Is my guinea pig allergic or something to the new hay? Is his sick because of the change in weather? Should I take him to see a vet? (I will probably not be able to get in until the middle to end of next week).