My 6-month-old Daughter Had A Yellowish-greenish Discharge From Her Vagina

My 6-month-old daughter had a yellowish-greenish discharge from her vagina in her diaper. She recently had gastroenteritis, but it has been 12 days and she is still having random vomiting spells, and still has very soft stool. Is it possible that she has a UTI? I don't suspect yeast because she was recently taking Diflucan for oral thrush.