I only had one reply, but will update you anyway....

By 10 am his nose had doubled in size and covered in red sores.

Vet thinks it is probably an allergic reaction, but possibly , and i do hope not, caused by a slight heart murmour and high blood pressure.  He has had 2 jabs, antibiotics and to reduce swelling, and has to go back Monday.  He is fine in himself and it doesnt seem to hurt or bother him, so fingers crossed it will disappear.

I hope everything turns out to be okay with your dog.  good luck.

#Warm regards Susan