Yes they usually are. These are far more common than you think, even for you. They come and go unless you are looking hard which you were owing to the encounter.
So what would that single pimple be? Just a pimple? Thanks in advance
All sex carries a risk. The odds though are 1 in many thousands. You need to go on symptoms that emerge, which they most likely would upon infection.
You have had no herpes symptoms so no reason to suspect a 1 in many thousands chance came up for you.
You don't think the brief vaginal intercourse poses a risk?
Nothing complicated about this. Your symptoms in no way resemble herpes. As a male with oral HSV1, it is virtually impossible to obtain a genital HSV1 infection meaning receiving oral sex poses no risk from someone who has oral HSV1.
Your test will simply reveal a positive for HSV1, your oral infection.