Hi, I am Dr. Peter and would like to help. Great history, but I need you to answer a few questions for me to give you the best advise.
1- How many times as he vomit?
2- Any diarrhea?
3- Did he eat something out of the ordinary?
4- Is he lethargic or continue to be the same?
It sounds like he may be having a simple gastritis (upset stomach), this is what you can do:
1- No food or water for next 12-16 hours.
2- Then, offer a small amount of water. If no vomit after half hour offer a little more and wait another half hour.
3- If no vomiting after water then offer a small amount of rice and chicken or cottage cheese. If no vomiting after an 1 hour, then offer small amount through out the day. Following day wean to regular diet.
4- OK to give Pepcid AC 0.25mg per pound every 8-12 hours for 2 days.
5- If the vomiting continues then you will need to have him examine by your vet, it may be something more then a simple gastritis.
I will be online for another 15 mins if you have additional questions.
The bile and mucus is just that the vomit was so forceful juices came from the small intestine.
If he continues vomiting or lethargic; develops diarrhea. These would warrant further investigation by your vet.
Its hard to say what did it; but, I would think probably the excitement of being home.