Missing periods, already it’s time for it

Patient: I had sex with my girlfriend on fifth day of her periods(last month)… i came inside her. But she took i pills within 12 hours. she had bleeding next day as she does in her periods…. It’s already time for her next periods but she is missing it this time…. What are the chances of her getting pregnant? Or is it just the side effects of pills that her periods are delayed? I’m really worried and tensed as we don’t want to have the baby now…….

Symptoms: Missing period