What Causes Pain In The Vagina During The Intercourse?

hello i am 21 yrs old n its been 4 months that i got married n still not able to ve sex with my partner even after vaginal dilatation when he tries to insert i'll ve a pain n i get tensed n i'll not be able to allowe him insert it n i am not getting excited n my vagina is dry n no organsm is produced what do i do