Severe Yeast Growth In Throat After Taking Large Dose Of Antibiotics. Temporary Relief From Medicines. Solution?

After taking a large doze of antibiotics during glandular fever and associated problems, like throat infection, glands infection, bronchitis etc, I found myself with a severe growth of yeast in my throat. It remained misdiagnosed for a considerable time, about a month ago, finally, I was at it seems correctly diagnosed, prescribed nistatin (do not remember the exact name), told to gargle with betadine ...I did it, I do not see a significant improvement, I changed the diet, take Pau d'Arco, Olive leaf extract. I do not see much difference in my throat, I have very little energy, do not sleep well and have increasing memory problems. Is it possible, I was misdiagnosed again ? Or if not, what else can I do. I am 62, though probably my biological age might be lesser, I am pretty fit and generally healthy, law blood pressure etc