Discharge after sex

Ok so I know what discharge of a yeast infection looks like but for some reason i didn’t have any till I had sex with my boyfriend after sex he always washes off and he said “babe I think you have a yeast infection “ and he showed me his pe us and yup it was discharge like a yeast infection has anyone else experienced this? And what the best over the counter treatment cuz my doctor isn’t taking any appointments that aren’t Emergancy