i have what it looks like a chancre on my penis shaft, it is located right on the outline of my penis shaft, im a circumsised man, and the outline of the ulcer was not firm it was black just like my penis shafts line, it looks round but not a firm round, the middle of it was just a shiny skin, painless and is not a open sore, it was never firm, as if my penis is flacid, the uthing that look like a chancre can be seen, the shape of it is still there over than a year, my question is could i be infected with syphillis? i saw that ulcer the day after the intercourse, or is it may be a eroded skin? and can syphillis be detected with only a normal blood test or the rapid home kit test?