Hello, I would hope to see improvement after five days. I would take my child to the pediatrician to see if antibiotic needs to be changed or dosage increase. Certainly do not delay if symptoms have gotten worse or additional symptoms such as a fever have developed. Severe tonsillitis will take more than five days to treat and chronic tonsillitis may require more than medication if not responsive. It is important to have your pediatrician follow the progress. Additional diagnostic testing may be considered since you have ruled out Strep. The coating on the tongue can indicate a secondary infection such as an oral yeast infection. Make sure you have followed proper dosage instructions. Thank you for your inquiry.