hi there, you have got a reinfection of the tonsils either from exogenous source or from residual infection which did not get totally eleminated by amox. You need to get a throat swab culture done and then started on the antibiotics which the microorgnisms are sensitive to.Amox+clavulanic acid
combination is much more effective and you could start on that with the help of your physician. You could also take anti-inflammatory pills to ease the pain and congestion. Take care.