If you really want to know if you have HSV 1, you could do the western blot. it is likely to confirm as positive. Have you ever had a cold sore on your lip or nose? If the answer is no, then you cannot know if your infection is oral or genital. Yes, this infection is very common. In terms of disclosure, I think I would simply tell partners, before giving oral sex, “i have tested positive for the cold sore virus, but I’ve never had an outbreak anywhere.”
If you have ever in your life had a cold sore, that’s why you have antibodies. But if you’ve not and have received oral sex, then it is possible that this infection is genital. Without an outbreak, it isn’t possible to know where your infection is.