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It sounds like Rolo is having a vaccine reaction. We can see a vaccine reaction as long as 24-48 hours after the administration of vaccines although the most common time frame is within a few hours of the vaccine. Because of the possibility of a vaccine reaction, my best recommendation is to take him to a 24 hour emergency hospital for treatment. If there is no hospital in your area, you can try to give him benadryl but since he is vomiting he may not hold this down. The dose used is 1-2 milligrams per pound and you can use the over the counter human product.
Other treatment for vomiting includes anti-nausea medication, antacids and fluids.
If there is no emergency hospital in your area I recommend calling your vet first thing in the morning to make an appointment to have Rolo seen.
There may be other causes of vomiting so diagnostics may be indicated before determining the appropriate course of treatment depending on the physical exam findings.
Does this help to answer your questions about Rolo tonight?