If you're trying to figure out when she is due, you might be able to figure it out from when she was in heat (you mentioned bleeding) or from when you saw mating activity.
If you made a note of the date, then that's easy.
But if you don't remember the exact date, you might remember some date that was close (like someone's birthday, or a particular holiday, or part of Spring Break, or the day the repairman came to fix something, or the day before Grandma came to visit, or any other noteworthy thing.)