From all you say, I see no worries about syphils or other STD. Kissing and protected vaginal sex carry no appreciable STD risks.
Syphilis could cause a primary lesion (called a chancre) on the tongue, and could be acquired by oral sex. But it's still not an issue for you. Syphilis is an uncommon disease, with only around 20,000 cases per year in the entire US, most of them in gay men. More important, it is not possible for a syphlitic chancre to develop while taking the antibiotics you have had. Most cases would be prevented by azithromycin (Zithromyax) and all cases would be aborted with with doxycycline. At this point, there is no need even to test for syphilis.
Could your tongue sore be another STD, such as herpes? Conceivably, but unlikely. However, the only way to know is to see a provider. You simply cannot get definitive answers by this forum or from any other online source.
This forum absolutely stays away from moral judgments about people's sexual behaviors (as long as there is no potential overt harm to another person). I do not judge your your actions and therefore do not disapprove them. However, you obviously disapprove of your actions. That is cause for concern, and probably for professional counseling. Further, you had a similar story about your emotional concerns over STD risk and fear of seeing doctors about STD in another thread 6 months ago.
Anyone who says "I seriously need help" clearly does need it. That is the only health problem reflected in your questions; STDs are not. Please bite the bullet and see your primary care provider, ask about the oral sore, but also be up front about the obvious emotional problem; and then follow the advice you are given, including professional mental health care if your provider suggests it.
I hope this helps. Best wishes-- HHH, MD
Thank you for you advice I will do my best to abide by it. I am getting help for my compulsive sexual behavior and the next step will be to see my provider. I have an appointment with my provider pre-booked for an unrelated issue on Friday and will show the sore to him and ask for STD screening.
Thanks again I appreciate your compassion.
I'm sorry, one final question and I will not continue with the thread. How should I explain my emotional problem to my provider? Should I say I am having a great deal of anxiety over fears of STDs? I'm not sure how to describe my problem.
You obviously are articulate and intelligent; just start talking about it. You could use pretty much the exact words you have used in this thread, starting with the last paragraph of your opening question. You might even describe my reply.