No, a syphilis sore, called a chancre, wouldn't last this long. It would be an open, round, painless sore that lasts about 3-6 weeks. At some later point, you'd get a rash on your body, often on the palms of your hands or soles of your feet, or your torso, which would last about 2 to 6 weeks, and may come and go. This can last for a couple of years.
After that, you may not see symptoms, but you still have the infection.
It's never a small little white bump. You can have a doctor check yours, but it's probably a pearly penile papule. I wouldn't think a genital wart, either, with it being there for over 3 years.