It's been a while since I was hit, but I didn't see a big effect because I tend to have a jaw bone itself rather than a muscle. But when I feel that my muscles are shrinking, should I say that when I touch my chin, I feel like I'm touching the bones, not the muscle I had before? If it's a side effect, is it twice a month? Now that I think about it, it's more like bleeding than menstruation. I haven't been hit since then!