s quite common
for oral sex to result in a genital fungal/
yeast infection actually. What is a normal fungus in the mouth, isn't always so normal when introduced into the genital area. Prolonged, unprotected oral sex for a half hour, is very likely to transmit this.
since you've been on an antibiotic, really no benefit for any urine testing for std's a this point. I'd start using the antifungal cream to treat the spreading yeast infection genitally and go from there.