Severe watery diarrhoea and tummy (abdominal) cramps: signs of a serious bacterial infection of the gut - Clostridium difficile infection.
Shortness of breath, hives, rash, swelling (of the lips, face, or tongue), fainting: signs of an allergic reaction.
Vaginal itching or discharge: signs of vaginal thrush.
White patches on the tongue: signs of oral thrush.
Being sick (vomiting).