I dont think you have syphilis.
There are different guidelines on the window period.
I dont think it is necessary to retest, but u can do so if u want.
Hi, like i said, it depends on which guidelines u follow.
Generally both is fine. A test at 12 weeks is not necessary, but u may do so if u want.
No, chancre dont disappear within 24 hours.
A chancre is not going to disappear within a day.
Seriously, you are going way overboard with the testing for a brief kiss.
HIV is never spread by kiss - ever, no matter what, nor is hep B. (Are you vaccinated for hep B? There is a vaccine available for that which you should talk to your doctor about.)
Gonorrhea and chlamydia are not spread by kissing.
Herpes type 1 may be, but with such a brief kiss, I'd be VERY surprised if it was.
You really have nothing to worry about here, and at 6 weeks, I wouldn't even worry about a cold or the flu, which is what is usually spread by kissing.