Maybe you could do some research on how a woman's body works and when/how a woman can conceive, maybe that would help you get a little more clarity that she's more than likely not pregnant
You just asked this same question....no it doesn't make a difference when her cycle came.
If she stared her period than no she's probably not prego. And yes u can get pregnant on birth control but she has to be super furtile. Its a genetic thing I think so if her mom got pregnant on bc she could possibly as well
Does it make a difference that her cycle came two days after we had sex.
Anytime you have unprotected sex you risk becoming pregnant. Use protection to avoid this as well as STD's. If she started her cycle as she normally would chances are shes not pregnant. After her cycle finishes wait 2 weeks and take a home preganancy test using first moring urine. But I think you should be fine. BUt Take this as a lesson learned because you only get so many chances before it does happen. Always, always protect yourself and your partner.