I assume it didn't happen when you first started having intercourse??
Is your husband especially big or are you very small?? If you had a child & had stitches you may have had 1 or 2 too many stitches. Other than that you shouldn't be bleeding (unless you're using a sex aid that is rough) so I would ask to see an ob/gyn or even see another ob/gyn if the first can't help. Also get another pap smear done, sometimes they are not accurate & maybe there is a problem that didn't show up last time or ask the ob/gyn to examine you internally. I think something must be wrong, unless one of the possibiles above aplies, especially the sex aid.