Is Post-Mortem Salvation an Orthodox Doctrine?

Questions about whether post-mortem salvation is an orthodox doctrine, reconciling a verse about God removing our transgressions from us with verses about each of us having to give an account to God on judgment day, and how to recognize true conviction of sin by the Holy Spirit.

• Is post-mortem repentance and salvation an orthodox doctrine?
• How do we reconcile Psalm 103:12, which says, “As far as the east is from the west, so far has He removed our transgressions from us,” with Matthew 12:36 and Romans 14:12, which speak of each person having to give an account of himself to God on the day of judgment?
• How do we tell the difference between conviction of sin by the Holy Spirit and feelings that are just either scrupulosity or the devil’s accusations?