I understand how worrying this must be. Sudden painful and frequent urination in your daughter is likely due to an underlying urinary tract infection (UTI), which may have actually been the original cause of her fever, rather than a direct side effect of Crocin DS (paracetamol). Dehydration from a fever can also lead to concentrated, irritating urine.\n\nFor immediate steps, encourage her to drink plenty of water to help flush her bladder, and avoid bubble baths or harsh soaps. Please have her evaluated by a pediatrician soon. They can perform a quick urine test and provide the right treatment to make her comfortable again.