Hi,Thanks for query,
If you have done full course of Penicillin then nothing to worry.
Many a times test shows positive after treatment even it is cured.
See that there should not be fresh infection having sex relation with infected person.
There is special tests are available like TPPA,TPHA.
At the same time you should go for testing of other STD
,Hep.B. virus as antibodies
og these STD may interfere this test.
Ok and bye.