mama didn't raise no fool

so ive been seeing this guy for about four three or four months. not really the best relationship ever, but for whatever reason we work through the hard times. well, about a month ago we both got all of our STD tests done just to have a nice reset and start to 'us' all of which came back fine. well, the other day, he mentions that he was having symptoms of gonorrhea and then insinuates he got it from me!! now i have not cheated at all mind you, so can someone explain how this is EVEN LOGICALLY POSSIBLE? im thinking he cheated and caught it and doesnt want to admit it. what do you all think??