i just found out i have an std

i went to planned parenthood last week and got tested... they called me with my results yesterday and turns out i have gonnorrhea. i went to the clinic yesterday to get an injection and antibiotics to cure it. and the crazy thing is...the guy i had sex with IS CLEAN. he got tested around the same time i did and he IS CLEAN. he sent me his papers and he’s clean! so i don’t understand how i contracted this because he is the only person i have been sexually active with.

update : his papers have the date on it so they’re not old papers and if i had it before then he would’ve gotten it. he’s the only person i have had sex with in the past year so i’m very confused.