A syphilis ulcer (at the point of infection) can show up between ten and 90 days after infection. It can last two to six weeks. The secondary rash (on the hands and feet) can show up two to 24 weeks after the primary symptoms have ended.
Syphilis is also called "the great imitator" because its signs and symptoms can be mistaken for something else. As with hiv, ONLY the appropriate test at the appropriate time can reveal your true syphilis status. Also as with hiv, syphilis can often be detected before the end of the three month window period, but a negative is only conclusive at the end of the window period.
If you're worried about syphilis, get tested. We cannot tell you whether you do or don't have it, only a test can.