Yeah, I have. I dunno what that is. I actually thought there were little crawlies of some sort in my hair, so I run to wash it. This usually only happens though if I really need to wash my hair or have a lot of product buildup on the scalp. Maybe it's the hair's/head's way of telling you you may have a little bit of buildup. Or maybe you just feel your hair growing. Or it's moving because the hair follicles are close to scalp muscle. I know it sounds crazy, but your scalp can move you know.