It’s very likely that the fracture couldn’t be put back together evenly. If the pieces of broken bone couldn’t be put back in place exactly, then the bone (and your leg) could indeed be shorter than it was before the fracture.
Ask your doctor to take an X-ray or measure you for a leg length discrepancy. Measurements with a plastic tape measurer should be taken lying down. The doctor can measure from your belly button to the inside ankle bone and compare the right to left legs. Sometimes the hip bone is used as the starting point.
You can also try an experiment at home. Stand in front of a mirror and put your hands on your hips. Use your index fingers to find the front pelvic bones. Are they level? Or is one hip higher than the other? Put a thin book or magazine under the foot of the leg with the lower hip. Keep adding layers of books or magazines until the pelvic bones are level.
Measure how thick the books are and try a lift the same height inside your shoe. If this works you can continue using a lift or have your shoe modified by a shoe repair shop to make up the difference. If you have any back, leg, or hip pain from doing this, have your
doctor or a physical therapist help you out.