Everyone has different risk thresholds. Catching an STD through oral play is possible but a lot less likely than through full intercourse. The risk of catching the more severe STDs is also a lot more unlikely through oral.
Cabergoline.
It lowers prolactin levels which is responsible for the refractory period after orgasm. It's something you let build in your system for a few weeks but personally the effect has been spectacular
HIV super low chance even she has it (less than 1%). Other STDs more likely (chlamydia and gono is 30% if she has it if I remember correctly).
Either way, get tested 1-2 weeks after the encounter and again in 3 months.