You really are lucky that piece of shrapnel didn’t do worse damage or hurt you or anybody else!! I know it doesn’t “feel” lucky to you, but many years ago I had a coworker who had a piece of steel similar to yours come through the floorboard of his Chrysler LHS and clip his calf! It was a somewhat minor injury that caused him surprising and significant long term problems. Very glad you are not injured!! Steel and paint can be fixed! If it’s any minor consolation to you, my car does not have a single panel that doesn’t have a ding or dent. I even have dings on the roof from flying debris. My car seems like a 460hp catchers mitt.