Please do get it taken care of. I most likely picked up syphilis this spring at a Bear Run in Dallas. Being a bottom, the initial infection chancre must have been internal. I didn't notice anything until I developed a rash this summer. Unfortunately, it started the week after I had spent an entire Saturday pulling vines and clearing brush in our yard, so I thought it was a reaction to some plant I was allergic to for the first week. By that time I had red dots all over my arms and legs. Fortunately, my doctor recognized the rash as most likely secondary syphilis right away. After tests confirmed it, I got a big shot of penicillin, and I was better in a few days. But the rash took weeks to completely fade. And everyone I ran into wanted to know what was up with it. Then there was the added joy of contacting every trick from the period when I might have been contagious.
Syphilis doesn't get dangerous until it goes past the 2nd stage, but it is truly no fun. Get it looked at now.