That sort of sexual exposure further reduces the chance this is syphilis. If the spot persists or flares up again, get examined. Most likely it's a minor issue that can be easily treated.
My sexual encounter was about 3-5 min. of receiving unprotected oral sex and about 10-15 min. of protected vaginal sex. I am in the U.S. (Southern California), and my sexual partner was not a sex worker.
The quoted phrase from the web raised my concerns because I had a circular spot on my penis head that did not feel painful. I guess I am just a little paranoid. The dry spot has since decreased in size..and sort of peels off little by little.
Thanks for your help doc!
Welcome to the STD forum.
It would be helpful to know more about the sexual encounter. If you are in the US and your partner is not a sex worker, and not an ethnic minority from the southeast part of the country, then the chance she had syphilis is virtually zero. Syphilis is rare in the US, with only 10-15,000 new cases per year in the entire US, with 2/3 of those in gay men and the rest mostly in the population groups just mentioned.
Second, your lesion doesn't sound remotely like syphilis. Among other things, syphilis cannot start the next day; 10 days is the earliest, usually 3-4 weeks or longer, as you learned. The photos you found on the web are typical. And from your description, I guess I don't fully understand why you found the quoted phrase of any concern. What you describe really doesn't sound at all like the description from the web. Am I missing something?
Most penile rashes or skin anomalies of the type you describe are not due to any STD, so it is unlikely the spot on your penis has anything to do with the sexual encounter 8/17. Most of the hundreds of causes of skin rash anywhere on the body sometimes involve the penis. If you are convinced it is abnormal and doesn't clear up on its own, see a health care provider. But I see no reasons to be concerned about syphilis and do not recommend testing for it.
Finally, I agree the oral canker sore is probably unrelated to any of this.
I hope this helps. Best wishes-- HHH, MD