Last week I got extremely drunk and at the end of a string of terrible decisions I had sex with a sex worker...I am trying to move on but need a little help and advice. 

I am a paranoid about catching (and passing on to my s.o) something and 2 days later noticed a very small patch (2-3 mm) of red skin in my pubic area, in my heightened state I thought it could be a sign I caught something but the more rationale side thought it was probably an ingrown hair, but I did not find one. Periodic squeezing and routing around with tweezers has coincided with making it look worse and more like a chancre (in between being covered with platers/cream, which does not seem to help) - is it possible that signs of syphilis could start after 2 days or even the red macule starts with 10? Clear liquid oozes with squeezing and it is looking more and more ulcer like. 

I'd like to put this behind me and move on but this is a niggle that I am grateful your services could help to resolve. Should I be worried? The sex was protected. 

First, congratulations for having protected sex in this situation. Second, no STI is a likely cause of the symptoms you describe and certainly not syphilis. No STI results in just a patch of red skin or mimics an ingrown hair, the location is wrong, and onset only 2 days later is too fast, especially for syphilis (which cannot show up sooner than ~10 days after exposure). In addition, in the US and most industrialized countries, the frequency of heterosexually transmitted syphilis is low. The pubic skin problem probably has nothing to do with the sexual exposure described, unless maybe a little physical irritation if that part of your pubic area was in vigorous contact with your partner. Probably you have delayed healing by squeezing and tweezing it -- lay off and let it heal (which might take a week or so).

You might wonder if you should be tested for common STDs. It's certainly not necessary based on what you have described, but some people test for reassurance even when the risk is zero or close to it. A urine gonorrhea/chlamydia test will be valid once 4-5 days have passed since exposure (although the risk for these was very low with condom protection, assuming you were not also exposed by oral sex before putting on the condom). Blood tests for syphilis and HIV are conclusive after ~6 weeks.

I hope these comments are helpful. Let me know if anything isn't clear.

HHH, MD