Diarrhea & Birth Control

Okay, so I know that if I vomit or have diarrhea within a few hours of taking my pill, it’s considered “missed”.

My question is...do I just continue you with my pack? How long do I need a backup method for?

The instructions that come with my BC just says that if you miss a pill, take it when you remember..,that’s not really an option, sooo...some answers would be appreciated!