Birth control

Ashley

This is probably a dumb question but my friend is on birth control , she tho that Saturday was Sunday and went to get a new prescription for bc and started the Sunday pill it’s yellow and she didn’t take her Saturday pill that ones brown and she took the brown one the next day instead of the yellow if this makes any sense . But she had unprotected sex and he finished in her while she was also on her period could she still get pregnant ?