How long should we expect to wait till she starts to Bleed? Is there a good chance she is pregnant? She wasnt expecting her next cycle till the 21rst of Sept.

My ex took the first next choice tablet yesterday, about 69 hours after we had sex. Then took the 2nd tablet 12 hours later as instructed. The next choice brand says take the pills within 72 hours of unprotected sex. She still has not started bleeding.