@Will Henry Do you have a patreon, or other ‘support’ site. I am very invested in your story and books and would like to support you more directly if possible.
According to bing chat bot. (who did all this digging and math)
The Kinetic energy of a Penny (2.5 g) when launched from a Slingshot with a velocity of 200 fps would be 0.053 joules
The penny is approximately 1.52 mm thick and has a diameter of 19.05 millimeters. If the Penny hits with the edge so most force would be transferred. The Area would be 0.785 mm^2.The Pressure of this area with a force of 0.053J would be 67.5 megapascals.This is equal to a PSI of 9,790 psi.
According to what Bing has found the force needed to break a windshield ranges from 9,400 PSI – 24,00 PSI.
So in the real of possible. (Note that in this math its a point blank shot as well)
The knight ordered food for her because he was going to be late.