Baby with a fever

A

My baby has had a low grade fever since she woke up at 10 shes very fussy she is 11 months I've given her tylonel all she wants to do is sleep when shes awake she just cries and cries this is her first time being sick just wondering how long should I allow it to go on before taking her to the er and should I rotate with tylonel and motrin every 4 hours?