This is quite an unusual happening to me or my circles. I find it quite weird to hear that someone woke up with marks all over their faces if they were not fighting with someone in their sleep. Usually i would say or rather think that you were fighting in your dreams with someone, or there was some kind of spiritual attack on you, because really how do you explain this kind of thing. I would understand if it has happened to you once or twice but if it is an everyday thing, then you can be rest assured that it is not normal. You could be fighting with dark forces and you are not aware of, i feel like this is something that should not be ignored or taken lightly if it is a genuine story. Over the years there has been stories where people have talked about being attacked in their sleep, and after being interrogated, they agreed that they could have had a demon attack, how true this is i cannot affirm, but it could be something like. Demons are real and they exist so i wouldn't refute the fact that someone can be attacked while sleeping. Maybe you need to pray about it ans see if it will stop happening. I don't know if i believe in that notion of scratching one self, would you scratch yourself so hard and miss to feel the pain? i don't think so.