Could she be peggo? NEED ANSWER SOON! (like 10 minutes soon.)?

Okay, my girlfriends last period was june6th or something near there. A period tracking app on her phone said she was due june 22nd for another period which she thought was weird. Naturally, she did not start. We had sex on the 17th. condom and pull out. The whole app thing has my head all twisted and im kinda nervous. What do you think?