Bright yellowish diarrhea & upset tummy gas was bloated started yesterday afternoon after cottage cheese (lactose sens)now fever 100.3 lactic acidosis?

Gastroenteritis. . My first thought in this context might be that the cottage cheese was bad. Was it sitting out for a whole? Did it taste bad, or sour? Are you nauseous? Vomiting? If your symptoms worsen or last more than three days then visit with local doctor for evaluation. .
Diarrhea. The presence of fever suggests that the cause of the diarrhea may be a viral intestinal tract infection. Lactose intolerance may cause similar symptoms without fever. Lactic acidosis, a severe metabolic derangement, would not apply to your symptoms. Your treatment consists of rest, intake of adequate room temperature fluids, Tylenol, avoidance of roughage, kaopectate as needed for diarrhea control.