hi
just a quick need for opinions:

took puppy (9mnths) to park - had a little run and then started tearing after other dog - they played a while - then puppy was sick. Very strange - he's never done this before. He had  been also walking on lead but he really pulls and strains - i am wondering if it is a result of the straining then tearing around?
thanks for advice

Guest there is vomit and vomit, you will need to joint to let us know what sort of vomiting it was in this case. But if it was just the once, and there was no other signs, I would not worry.