Paul the Apostle didn't spend his early career as either Paul or as an apostle. He was born into a devout Jewish family in the large Mediterranean trade center of Tarsus, one of the most prominent cities in Asia Minor. He was of the tribe of Benjamin and while he was still quite young he studied under Gamaliel, a very well respected rabbi.
He was known as Saul of Tarsus and, far from being a proponent of Christianity, Saul made it his mission to persecute and put to death early disciples of Jesus in the area of Jerusalem and beyond. He took part in the killing of the first Christian martyr, Stephen.
Although first Mary and then her fiancé, Joseph, were obedient to God and His will, it could not have been easy. They had to live with the fact that those around them would never likely believe their stories about why she was pregnant before marriage.