Very unlikely. The egg doesn't just hang around in the uterus waiting to be fertilized, so unless you ovulated very late you should be in the clear! Stranger things have happened, but you should be good to go :)
Thank you both so much for answering!
Very very unlikely - I wouldn't make it a habit though. Using protection every time is your best course of action. Good luck.
It's possible bc your egg is fertile right now and doesn't shed till you actually start bleeding.. Best of luck