I agree with GuitarRox. The chance that this is herpes causing just burning after all this time is very, very slim.
You had protected oral and vaginal sex. The chances that you'd get hsv2 from a one-time protected encounter are about 1 in 10,000. (We don't have the same studies on hsv1, unfortunately, but it's also assumed to be incredibly low.)
LP can be awful to deal with, and I'm sorry you have to. Here's some pretty basic info about it, but may have things your docs haven't tried (light therapy, allergy testing, etc) - https://www.mayoclinic.org/diseases-conditions/lichen-planus/diagnosis-treatment/drc-20351383
You mention the lockdown for covid and anxiety. Don't hesitate to consider therapy for this. It sounds like you're in a high covid area. I am, too, and it isn't easy. Don't underestimate the trauma we're living through here. Talk to your doctor about your anxiety, get a referral to a counselor, or try one of the online therapy sites, like TalkSpace or BetterHelp. Many counselors that are covered by insurance are also offering phone and online sessions now, too.
Looks like this forum is dead :(
I was hoping a response from some experts though based off reading other posts, it looks like I do not have HSV but the symptoms could be due to some other reason.
Would have loved a response for some reassurance though.
Also note that I am otherwise in a monogamous relationship and this August incident was the only incident between 2016 (when HSV was ruled out and I was diagnosed with genital lichen planus) that I had with someone of unknown status. I want to get to the root cause of the burning sensation and want to be symptom free. I have read online that herpes symptoms typically never last like 3+months though. So, I needed some clarification from you experts as well.
And yes, I have severe anxiety issues, especially with the WFH situation and social distancing, my anxiety is at its peak.