Hello & welcome, I am Dr. B, a licensed veterinarian and I would like to help you today. I do apologize that your question was not answered before. Different experts come online at various times; I just came online, read about your wee one’s situation, and wanted to help.
Again I do apologize that my colleagues could not aid you sooner. If you would still like assistance, can you tell me:
How long has he had these signs?
Would you say he is coughing/retching up the mucus? Or actually vomiting?
Any discharge from his eyes
Has he been eating? Can he keep water down?
Are his gums nice and pink (not white/pale)? Moist or sticky?
Could he have eaten anything he should not have (ie bones
, stones, socks, toys, plants, chemicals, human meds, etc)?