I had sex with my boyfriend a week ago, and now i have this itching in my vagina, is it possible that my boyfriend gave me a yeast infection?

Maybe: the normal pH of the vagina is quite acidic, and sperm is alkaline, so ejacuatlion can cuase a change inthe pH balance that can make yeast more likely to grow. You may want to get checked for other infections that are sexually transmitted, such as chlamydia and gonorrhea. New soaps or wipes can make you itch! Also, condoms do not protect against HPV or herpes--so take care