This doesn't sound any STD and definitely not syphilis. Even if it were, you are on the wrong drug. Ciprofloxacin is totally inactive against syphilis. Stop taking it and see your doctor.
I know its stupid but I've been self medicating Ciprofloxacin AL 250mg as i thought it could be sithylis and hopeful this would clear it up.
You should see a Dr for an exam, not sure what they could be.
They are yellow and puss filled and it would tie into me as an STD as I've been giving oral sex to a couple off men in the last few weeks.