Question About Mono

i found out that someone I had began kissing three weeks ago and
stopped kissing one week ago has mono. I do not remember ever having
it, though I have possibly been exposed to it as a child (I'm 23). I
understand that I would not yet be symptomatic, and that there is very
little I can do. I'm getting a physical monday, and will be tested
then for mono (will the test even be acccurate?), but have another
date this weekend i want to make out... my question is how contagious
am i now? technically i do not know that i have mono so i don't
know,...
thanks
mjs

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