Without seeing the photos. likely that the ejected round is striking part of the rifle. Unless you have a major crease, those usually iron out on reloading. The M60 MG was famous for flattening one side of the case mouth of fired cartridges. REALLY strong ejector on those.
A ding in the side of the case body is not uncommon. Generally minor and does not interfere with the loadability of the case. My HK-91 pounded the cases until I put a port buffer on her. Never caused an issue. Resizing removes most of it and the pressures of firing irons out the rest. Ejection promplty leaves a new dent. I may shorten case life by a loading or so, but not a big deal.