Could she get pregnant?

I know, I know another pregnant question, but I am just worried for my best friend. She just started a new birth control like 3/4 weeks ago, and about 1 week after her period( a couple weeks ago) ended she had breakthrough bleeding or another period(not sure) and she had unprotected during it. Then a week after it stopped she had unprotected again repeatedly I told her how stupid it was she's only been dating this guy for a month and half. Is there good chance she will get pregnant? I think there is but she seems to think not....