The HIV virus requires a period of time longer than two days after risky intercourse in order to weaken the immune system and for a yeast infection to appear. Yeast infections are related to HIV because HIV attacks the cells of the immune system, thus allowing certain rare infections to occur.

Therefore, The presence of a yeast infection in the mouth or throat, which is rarely found, can raise a suspicion for an HIV infection.

Please note that a yeast infection might be easily found on the nails in a person that get their feet wet (usually from sweat) more often and on the genitals in sexually active persons soon after intercourse.

In your case, it is possible that the yeast infection might have been transmitted from your partner by the unprotected sexual intercourse you mentioned. A yeast infection of the toe nails can be unrelated to a penile yeast infection.

Under the supervision of a dermatologist, you might try applying antifungal cream on the nail and the surrounding skin for a longer period (several weeks). Alternative treatments which might be helpful can also be offered if you schedule a visit to your family doctor or dermatologist's office.