What you describe sounds exactly like the symptoms Lady had when she had HGE. "Raspberry jam stools" are classic HGE. Yorkies are prone to it. If Sushi does have HGE, he needs to be seen by a vet immediately. There is no home care. HGE can be fatal.
"In addition to producing diarrhea that looks like raspberry jam, canine patients appear tired and weak." Hemorrhagic Gastroenteritis in Dogs - Whole Dog Journal Article Hemorrhagic Gastroenteritis (HGE)