swollen lyphme node in femoral area of left leg

[rightnow123]

hi i am really sorry to disturb anyone, but i would be much great full if some one could answer my question. when i had a exposure to a prostitute  year ago which was protected but since that i have tested many time and i have come negative for all my STD test, however its been like 8 months after the last time tested for gonorrhea where they did a swab culture which was also negative, now i have   a femoral lymph node on my left leg which is swollen you can feel it and its stiff for like a week and  a half and i have no other exposures, unless my friend injected me in my sleep which would be OCD to consider such a thing.
what can this swollen lymph node be on my left leg please help

[rightnow123]

thanks mate just so tense about the cause i really did not expect this, thanks for the input mate

[Teak]

Not an HIV concern.