I had sex with a friend of mine from New Zealand a few months ago. We used a condom, but as we were a bit drunk he inserted without first putting it on (very irresponsible, stupid, stupid thing to do). About three weeks later I woke up and my left outer labia was quite swollen. There was a pea-sized lump under the skin, it was a bit red and sore to touch and I could move it around like a swollen lymph node. I did a bit of research and was under the impression that it was a sebaceous cyst. I tried to pop it on the first day, but just aggravated it. After two or three days and a few hot compresses, I popped it. There was a lot of pus and a little bit of blood. I am not sure if there was a hair or not. I shave regularly and it was in an area with hair follicles. After I popped it it felt like a deflated pea, scabbed over and healed after a few days. In total, I think I had the lump/scab for about a week.
A few weeks ago I went to get my three-year cervical smear and also requested to be tested for chlamydia and gonorrhea, which came up clear. I didn't even think to ask about the lump because I was sure that it was a cyst.
However, over the past two days I have suddenly become terrified that it may have been a chancre. I have had no other noticeable symptoms that I am aware of apart from a winter flu, which I hope/assume was related to winter weather and the fact that I have always gotten sinus infections really easily.
Does this sound like it could be syphilis? I am mostly concerned because of the timing. I got the lump about three weeks after sexual contact.