Ugh, so you need a different antibiotic it sounds like. Strep can be resistant. Amoxicillin unless in high doses or mixed with clavulanate acid (making the brand name Augmentin) can be ineffective and the azithromycin add on really sounds like an odd choice to treat strep. Call your doctor and tell them you are not improving. You normally start to feel better within 48 hours on an antibiotic with lessoning of symptoms (always take the full course of the medication though even if you feel better). With PANDAS and other strep related complications, get it knocked out. good luck