Keep in close contact with your vet. Let him know that Bailey is still having blood in his stools. I honeslt do not think that he is terrible sick . He is showing know other major signs of illness, playing like a normal little puppy, and having a great time.
This is why it is important to keep taking him back to the vet , bring a stool sample , and let the vet figure out excatly what is going on with your little guy. Sometimes it can take a while to cure a nasty bug . but, it will get cleared up! He is going to be OK!
Just remember that your baby is healthy otherwise, and you are doing all the right things for him. He is happy, energetic, playful, eating well , and all those wonderful things a puppy should be doing . He should be OK !