I doubt it. Of course, I'm not a pathologist, but I don't think a virus can mutate in such a short time period. And just taking casual evidence into consideration, I've never heard of anyone saying that they had a SV and then just three weeks later saying that they got another one. That would just be such terrible luck, I feel like it wouldn't happen. To lessen your anxiety for your reunion, just be ultra-super-careful about hand washing and touching food, your face, and mouth until then, and then you can reassure yourself that there's no way you could have contracted a SV because you were so careful about what went in your mouth over the preceding couple of days, and you were not in the presence of anyone v*ing or having d.