I'm sorry I never followed up on your other questions. My dad died the day you posted in Aug, and I took some time off from posting in here.
I'd interpret as negative, too (though I'm not a doctor). You haven't had any symptoms, you were protected, and the chances of you getting herpes from a one-time, protected encounter are very slim. It's not something I'd worry about at all. :)
Had an HSV-1/HSV-2 type blood test a little while back, they came back indeterminate. Doctor interpreted the results as negative since the there is no confirmation of HSV-1 or HSV-2 and I haven't been sexually active since I started testing myself.
What did your test say exactly? Did it give you any numerical results?
The chances of you getting herpes from a protected one-time encounter with a female are very slim, and since you haven't had any symptoms, it's not something I'd overly worry about. You should probably retest, start with another IgG test, and go from there. I don't think you have a lot to worry about though, and think you are testing to just ease your mind.
Just to add I got the test done June 12 2018.