How would you know?

I have a random question. I’m on the mini pill because i was breastfeeding, but in my upcoming appt i will tell the DR to give me the regular pill since i stopped breastfeeding already. But i was thinking about something. For the pill you usually bleed on the last row of the pack on your “break” pills. But for the MINI pill theres no break in between packs and spotting can be random, or no spotting at all. So how would you know if you’re pregnant while on the mini pill lol just a random question.