Strep throat symptoms worse after being on antibiotics?

I was diagnosed with strep throat four days ago, and after taking the amoxicillin for two days I felt much better. but after 24 hours I forgot to change my toothbrush like the doctor told me to and I woke up yesterday with my whole right side of my throat sore and white spots there (when they did the culture it was all on my left side) and I changed my toothbrush. today I woke up and it's even worse. should I go back to the doctor?