OK there are very few people that indeed have real "accidental" pregnancies. These people are limited to folks that had surgerical procedures (women/men).
Meanwhile, being on BC and it didn't work or was 100% effective (another words you were the 1% out of that 99% odd) Im sorry but your situation is not an accident.
If you have sex, you are risking or taking the chance that you may end up pregnant at 1-10% using BC or higher. That is not an accident, that is simply taking a "chance".
Unless you "accidentally" had sex and then you got pregnant, then I will give you credit for having an "accidental" pregnancy.