Don’t get me wrong, I have committed many sins, however, they were not Mortal Sins.
In order for one to commit a Mortal Sin, one must do three things.
1. One must know it’s a sin.
2. One must contemplate committing the sin.
3. One must commit the sin.
Under these criteria, you have probably never committed a Mortal Sin either. However there are people who do commit Mortal Sins and they will burn in hell if they do not ask the forgiveness of the person or persons they have committed these sins against.