My vagina is itchy and every time i have sex with my partner his penis swells up and sometimes tears, what could be the problem and i have white substances that comes out ?

Yeast?: You likely have a vaginal yeast infection, which can also irritate a sex partner's penis. See a doctor to confirm. Or try an over the counter vaginal yeast treatment with a product with active ingredient ending in "azole" (miconazole, clotrimazole, and several others). They all work equally well; you can choose the least expensive. But for sure see a doctor if it doesn't work. Good luck.