I don't believe the devil nor other demons are going to scratch you or leave marks. If you are saved, the Holy Spirit has come into your body, and you are protected by Jesus Christ. The devil cannot touch you now once you are saved.
Now, look at those scratches in another light: what good would it be for the demon if they had cut you? We already know they're bad, but why should they try and prove it? More than likely, the cuts or scratches you have found have come from something else you've done and they have come upon you by accident. I know of numerous times where I've found scratches, skin roughed off, cuts, and I never know where they come from, but more than likely they have come from something I've done that day. I wouldn't worry of demons trying to harm you, Debbi.
If you are truly worried, there is only one thing to do: Pray to Jesus Christ and say "Jesus, keep the demons from me and hold me in your arms." Say to the demons, "Stay away from me, and do not tempt me!" You may or may not see less scratches or cuts, but at least you can put your mind to ease!
God Bless,
~Marc