abreva is barely effective for oral herpes. it was ineffective on genital herpes which is why they never sought out marketing for it for genital herpes.
as far as I know, tamiflu isn't effective for all viruses in general. I know of no studies that show it is effective for herpes.
should your symptoms reoccur, be seen promptly for a proper exam. otherwise you can repeat your herpes igg blood tests again 3-4 months post encounter as mistakeguy already suggested. This could be any number of things going on but at this point if symptoms are almost gone, not too much else you can do to figure out what really is going on.
grace
Forgot to say should you have a repeat of symptoms be seen within 24-48 hours for a lesision culture and proper work up.
The proper course of action in this case would have been to see your provider for a work up. The fact the bumps are gone isn't helpful.
Abreva doesn't have any clinical data to support that it does good and surpressing the HSV virus. They say they do but I haven't seen anything.
Condoms don't sadly protect well against herpes. Herpes is spread via skin to skin contact. So given you wore a condom you only protected part of you. Though the first typical outbreak is at the site of infection but can be anywhere in the boxer shorts area.
Testing was done to soon. You need to test after 3 months of the encounter for accurate diagnosis. Testing now showed your status prior to this incident.