I was diagnosed with mono!!! Advice???

I was diagnosed with mono yesterday, i have speckled white blotches on my tonsils, i was just perscribed prednisone and Codine........ when will the white blotches on my tonsils go away? its been about 3 weeks with mono, but my thoat got really bad the past couple of days, is there any antibiotics to cure these white blotches, super painfull even with painkillers.......HELP