I recently noticed a small almost like scab patch of darker hue skin on my anus. I have hemorrhoids so that area tends to get darker as the blood flows to it. but it's as if it was a mini burn look to it when my hemorrhoids don't swell, or a scab someone peeled off. I can't explain it. I have unprotected sex with my bf, we are both clean and hiv free. I am hypochondriac so I'm always thinking the worse. It if is syphilis, does the chancre sores start like this? or the hollow oval like shape at the get go. or is this an anal fissure that's finishing healing up?