Hi! I Had A Throat Infection A Couple Weeks Ago,

Hi! I had a throat infection a couple weeks ago, suspected strep throat and was prescribed a Z pack. The sore throat cleared up for about a week and then came back. I did another virtual doctors appointment and was prescribed doxycycline. I’ve just finished a full 3 days of antibiotics and my throat is still sore. My tonsils are very swollen and the sore throat switches sides. The soreness is focused on the tonsils. I’m starting to get nervous now because I’ve had a sore throat for so long. Is it normal for antibiotics to not resolve within 3 days? I’m starting to get nervous it’s a more serious issue. Thank you!