Scratching from going through forest makes the most sense because I've kept good track of everything else you mentioned and I didn't know that one was a feature. It would have had some time too since I've been focusing on building my base and haven't been in any danger and haven't had need to check health.
Thank you. Since I know to look out for the forest thing now Im not so worried that its a bug I have no way of stopping. That would have been the only time a forest ever scratched me though and its a little frustrating but there were probably good indicators like pain moodles or blood trails that I was just too relaxed irl to pay attention to.