Welcome to the forum and thanks for your question.
I agree with the advice you had from your doctor: I am confident you have no STD from the oral sex event and that neither your nor your main partner's symptoms are the result of any infection from that event. Shy? First. it was a low risk event: oral sex issafe sex, with low rik for some STDs and zero risk for others. Second, neither your nor your partner's symptomsare typical for any STD. Third is the negative results on your STD lab tests. Fourth, the symptoms of vaginal yeast infections are easy to recognize accurately by affected women, especially if she has had prior yeast infections and the symptoms are similar -- and as you probably know, yeast infection isn't an STD. Finally, there is another likely explanation for tiy symptoms: they are very typical for genitally focused anxiety, leading you to over-interpret minor sensations that you otherwise wouldn't notice or would ignore.
At this time, I see no need for you to see another doctor or for additional lab tests of any kind. If the symptoms continue, return to your own physician, then follow her advice if she recommends referral for a second opinion.
I hope this hashelped. Best wishes -- HHH, MD