What Causes Sore Throat Along With Pus Pockets At The Back Of Throat?

Okay so a couple weeks ago I had a really sore throat with white puss pockets in the back like strep. Went to the doctor and the rapid strep test came back negative but they said they were going to put me on amoxicillin cuz it still looks like it. They said they would still grow the bacteria and do another strep test and that they would call if i needed to stop taking the med. They havent called and its been about a week or more since i finished my dosage of med. i still have white stuff in throat no pain though. And i know how a small patch of medium sized bumps on my arm. Not itchy or painful.