My Baby Is 3 Years Old . One Day Suddenly

My baby is 3 years old . One day suddenly she started loose motion .and fever of103 degree .... temp ... doctor said .it's food poison and suggested Diof ds and Rinifol z
Even after 4 days .. loose motion was not cured .. then we had a motion test ... it reports that mucus is present n puscells plenty .. and it is 12 th day ... even then my child did not come out of loose motion ... it includes mucus ... green n yellow color ... what all this mean ... how long this infection prolong ... I am very mmuch worried