A core shot basically refers to any damage that exposes the core of the board (wood in most cases). These you usually want to repair quickly because exposed wood absorbs moisture which can rapidly lead to further damage. From the base, it usually takes a significant gouge, like from hitting a rock at speed, to penetrate both the p-tex base material and the bottom layer of fiberglass. I'm sure you didn't do one skidding your board on the floor. I'm sure your edges are fine as well from what you described. It takes a significant impact to bend an edge. I can relate to being obsessive about keeping my stuff pristine, but I've found with experience that it's liberating to just enjoy riding and not worry about it. I'd much rather go snowboarding than have a flawless snowboard.