She just started a yesterday, It is very thick and sometimes has small traces of blood

Take him to the vet. There are many things that could be wrong, parvo, worms, and other illnesses. We can't diagnose him online, please have him checked out by a vet.

Adam anyone who sells a pup under 8 weeks is usually a back yard breeder or some form of a puppy mill. 6 weeks is WAY too young to leave the pack. They learn the really important socialization skills with in the first 8 weeks. I am assuming that this dog has yet to be vaccinated or de wormed and de flead which my inclining for these symptoms would be parvo or parasites, be it worms, giardia or coccidia. The last two are very easily treated and preventable with the proper care. Parvo is easily preventable with the vaccine and can be treated. All can and normally will lead to death in puppies if not properly treated.

So sad, I hate those people.

I totally agree, get your pup to the vet as soon as possible. Puppies that age have little to no reserve to fight off illness, his best bet is professional medical treatment.

Good news, well sort of, I took her to the vet. The diarreha was due to the change in her diet, however she does have a heart murmur that may or may not go away as she gets older

I'm glad you took the puppy to the vet. The heart murmur is a concern, but now that you know, your vet can set up a plan to keep it in check.

Sadly, health defects are common with puppies improperly bred by either a backyard breeder or puppymill. Breeders do genetic testing on their dogs in order to produce the most healthy puppies they can. I know for a fact that your puppy did not come from a breeder because of the age the puppy was released.

This is why so many of us fight to stop backyard breeding and puppymills, dogs sold in pet stores. The health of these puppies is often poor, and can cause a lifetime of problems.

Now you know, and hopefully, next time you adopt a dog, you'll be prepared to weed out the backyard breeders and puppymills and get a dog from a breeder that knows what he/she is doing.

Good luck.

Please don't let your puppy outside until after at least the 3rd puppy booster!! Parvo can live in the dirt and be air born.