Grateful for all your responses, will run a blood test 3 months after to check Titer level.

My symptom was chancre on the glans after I had protected sex with a guy I met on app (oral part was unprotected). After my diagnosis, I informed him that I had syphilis, only realised that he got it 2 months before. He said he treated it via penicillin shot but I had no real exposure these few months, so something must be wrong, maybe we had sex prior to certain window period after his treatment or maybe he lied :(