Thanks for your query.
As per test child is having infection and pencillin was given.it takes 24 to 48 hours for medicine to act.
Continue with acetaminophen
every 6 hourly,give plenty of fluids,fruit juices vegetable soup and soft bland diet so as to maintain hydration and nutrition.
In case fever
persist after 48 hours get him re evaluated by pediatrician
Wishing your child good health.