VDRL test

my Q is not about HIV actually I had sex with a girl in a 1 night stand and it was safe sex with the condom and all, but I'm frightened like hell that she might had syphilis, I had my VDRL test 16 days after I had sex and it came out Negative, so is that long enough or I should have waited longer and than take the test to be sure the result is negative? How long dose it take for the body to start producing syphilis antibodies that will show in the test?

[Teak]

You'll need to post in the STD forum. This is not an HIV concern.