The best way to combat a sore throat is by drinking lots of good fluids such as water and gatorade.

Penicillin is an antibiotic. It only kills bacteria. Most sore throats are caused by viruses, not bacteria. So, those four pills you took most likely did you no good at all, except maybe gave you an upset stomach.

As for muscle loss, I have no idea. I don't believe that antibiotics can cause muscle loss.