Oopps typo !!! I meant I CAN'T give you a more reassuring answer ......
It does sound a tad suspicious that it could be Herpes I'm afraid, particularly when they appeared around a week after possible exposure as well as how you describe the lesions, you're Doctor should have taken a culture swab while the lesions were there and that would have told whether or not it was Herpes, you will have to wait 2-3 months now to have a blood test,but in the meantime if they appear again in those 2-3 months go to your nearest STD /GUM clinic and have them swabbed for possible HSV as soon as they show up again.....
I'm sorry I can give you a more reasurring answer
Daisy