If you had a cyst beforehand, sure. You don't always feel pain from a cyst the same month it formed (they typically form from an issue during ovulation, and mine was 10 cm by 11 cm before I ever felt it, and that certainly didn't happen overnight). Your ultrasound will pick it up if you have a cyst, though. You could mention it to your gyno at your next appointment and see if the gyno can have the ultrasound tech look at the ovaries, too.