Glandular fever.

[MCFCinUSA]

I wouldn't worry about it; you've probably been exposed already by her - if not in your childhood.

people all react differently; some don't even know they've got it and only get mild or flu-like symptoms.

(and just about everyone's got or had it because it's endemic, with around 1 in 20 suffering from any sort of complications - apparently going off the medical literature)

 

[117 M34]

I would have her tested for sti's that she may have also caught off the phantom kisser...she might have kissed him somewhere other than his lips