I Have Been Taking Pennicillin 500 Mg For 2 Days

I have been taking Pennicillin 500 mg for 2 days (more than 48 hours, and I will take my 6th dose in a few hours) and i have NO relief from sore throat. It might actually be getting worse. I'm taking Tylenol Extra strength and Ibuprofin on rotation every 4 hours, but they barely ease the pain. I've done warm salt water gargles and throat lossanges. Do i need to go back to the doctor? I cannot eat or sleep because of the pain.