Pain after being on antibiotics for days

My 4 year old daughter has an ear infection and has been taking amoxicillin since Monday, so 6 days. We haven’t missed a dose or anything.

She seemed to improve and fever went away the next day. But today she’s been complaining all day that her ear hurts again. She will wince and grab her ear suddenly. Is that normal? The antibiotics seemed to be helping so I’m confused why she’d still feel pain and seems to really be bothering her again today.