Yup...they will continue to grow until ovulation. Like Alexis said, they grow 1-2 mm a day, but closer to ovulation usually 2 mm, so I would expect that they grow an extra 3 mm from the time of trigger. Best of luck this month!
My RE's office told me they do continue to grow, the HCG shot gives them an extra boost and matures them. I triggered on Wed eve and mine were 16mm and 23mm on the left side and today so much pain they must have gotten bigger prior to O which I think was around noon from the amount of pain I had at that time.