Can you have cryptic pregnancy even if you took birth control pills?

I'm so confused. I have been watching videos where women don't know that they're pregnant untill they go into labour, which is called cryptic pregnancy. It got me wondering whether it is possible to get pregnant even after taking birth control pills ASAP, and not know that you're pregnant? I did have protected sex with my boyfriend using condom and immediately took the birth control pill to make sure I don't get pregnant. But after watching these videos I am a bit worried. Please help. I can't get myself checked and can't even tell anyone.