Hello Good Evening,
There are rare chances to conceive, if semen totally dripped in mouth, this is not a natural route of sex and getting pregnant.
It is looking rarest possibility of pregnancy
, semen taking to vagina from mouth by finger, even not knowing her fertile period according calculation of menstrual cycle days.
Due to many factors, there are very less chances to get conceive if semen is not ejaculated directly into the vagina of the female.
You should not take bother, be relaxed.
Dr. Naresh Jain