Took the yeast infection pill friday and symptoms came back

I took diflucan (yeast infection pill) and the pamphlet or whatever said that it could take up to 5 days to cure it even though it’s just one pill it stays in your body for that long. The day after I took it all symptoms were gone so I forgot about it but today, i have severe itching on the inside and opening of my vagina and I don’t know if I should take the 2nd pill the doctor gave me. He said take the second one if after 5 days the first pill didn’t work. I’m kind of in agony though