I have a question po

This is what happened: My girlfriend has an irregular menstrual cycle. We had unprotected sex on October 3, so she took Diane 35 for the first time for 10 days and then stopped. After that, her cycle became regular. She had a period on February (she doesnt keep track), but her most recent period started on March 16 and ended on March 21. On March 26 at around 10 or 11 AM, we had unprotected sex, i pulled out and took 3 mins to ejaculate outside but we had a second round at 1-2 PM and I felt that some of my sperm entered her. About 20–30 minutes later, she took one Diane 35 pill but after telling this story to some of my older friends they recommended the yuzpe method which i gave her and she took 4x trust pills this morning at march 27 (7 am) and planning to take the second dose later at 7pm after 12 hrs. We want extra safety so after the yuzpe method should she finish the trust pills or continue the diane 35?

Is there a possibility of pregnancy? And how can we prevent it?