Thanks for your query,based on the facts that you have posted it appears that you have developed clusters of small bumps near frenulum
after having a oral sex
by your girl friend.
Mouth is full of bacterial flora hence chances of getting infection through oral sex are very high.
You need to take broad spectrum antibiotics like Cefotaxime
along with anti inflammatory medication like Diclofenac
Ensure to wash your genitals with warm water twice daily .and avoid sexual activity till it gets cured completely.