Valley Fever? Hmm, not familiar, how would he have caught that?

As or the torn ACL, small dogs DO get that! Dogs who do Agility are prone to it. Any dog who jumps can land "wrong" and tear it. Just getting of the bed, a sofa or chair could do it. Going down steps and landing just plain wrong will do it too. THAT can be fixed, surgically if needed. The 6 weeks recovery is toughest; keeping the dog from running or jumping!

Pain meds are good while you wait for the test results!