can anyone help - my 8 week old puppy got her 1st jags on Friday and has been neither up nor down, today she is still very active but has had diahorrea, no blood found.

To be perfectly honest, it could be so many things and it would be unwise of anybody to offer you an online diagnosis.

Puppies are very susceptible to dehydrating from diarrhoea and, despite my years of experience of owning dogs, I would always pop a puppy that young to the vet promptly for a check up.

I would suggest that it's unlikely to be related to the vaccination as reactions to this would tend to be noticable much sooner.

may just be change of food/ environment. Try not to worry too much

i would pop to the vets to make sure as it's a young pup but it may be worth feeding some very bland food for a day or two if it continues.
i always feed mine rice and chicken if they get any tummy problems and this seems to sort them out pretty quickly.
with a young pup it's important to keep feeding them and getting them to drink plenty of liquids unlike with an older dog that you can starve for a day to help sort things out.
ask the vet what they think but pups tend to get a funny tummy sometimes so i shouldn't panic about it.